The NFL draft offers an introduction of sorts for a new crop of star athletes, but it's also a goodbye for the fans and schools these players leave behind. And now it's up to their college coaches to find new stars to replace them.
Let's look at some of the schools that will have first-round holes to fill in 2020, and who's involved in the battles to fill them.

LSU
Draft pick: QB Joe Burrow
Replacement: Myles Brennan
Thanks to copious garbage-time opportunities, Brennan took 128 snaps and attempted 40 passes as Burrow's backup last year (he completed 24 of them for 353 yards, one touchdown and one interception). If there was any possible chance of a battle between Brennan and redshirt freshman Peter Parrish for the job, that ended when Parrish was suspended this spring. This is Brennan's job, barring injury.
Draft pick: WR Justin Jefferson
Replacement: Racey McMath vs. Trey Palmer vs. Jontre Kirklin
The LSU receiving corps loses a lot (more than 2,900 combined receiving yards and 25 TDs, much of which came from Jefferson) and returns a lot (more than 3,000 yards and 36 TDs). The Tigers get Biletnikoff winner Ja'Marr Chase and junior Terrace Marshall Jr. back, but between McMath, Palmer, Kirklin and maybe Jaray Jenkins, it would be helpful if a third veteran option emerged. Blue-chip freshmen Arik Gilbert (part-WR, part-TE) and Kayshon Boutte could get a look, too.
Draft picks: OLB K'Lavon Chaisson and ILB Patrick Queen
Replacements: Jabril Cox vs. Micah Baskerville vs. Ray Thornton vs. Marcel Brooks
It will be interesting to see how new defensive coordinator Bo Pelini juggles things, potentially moving from a 3-4 to a 4-3 while managing a deep set of linebackers. Cox, an FCS All-American, arrives from North Dakota State, but veterans Baskerville and Thornton and blue-chip sophomore Brooks will all be battling to see the field next to junior Damone Clark. Lots of players, not a ton of opportunities.
Draft pick: CB Kristian Fulton
Replacement: Cordale Flott vs. Elias Ricks
Well, this one is more "or" than "vs." Flott carved out a niche as the No. 3 corner and occasional nickel last year; he allowed only 6.6 adjusted yards per attempt as primary coverage man, less than Fulton (7.0). But it's possible Flott takes on more of a nickel role this year, and that could open the door for Ricks, ESPN's No. 4 corner prospect in the 2020 class, to take over. (Sophomore Jay Ward could also play a role at either corner or nickel.)
Draft pick: S Grant Delpit
Replacement: Kary Vincent Jr. vs. Maurice Hampton Jr. vs. Cameron Lewis vs. Jordan Toles vs. Todd Harris Jr.
Pelini inherits an embarrassment of riches in the secondary. Vincent (also a track star) could fill the nickel role instead of Flott, or he could fill the role Delpit leaves behind. Hampton (also a baseball star) could compete for a role if Vincent's at nickel. Lewis is a jack-of-all-trades, Toles is another incoming star freshman, and Harris was a 2018 contributor before tearing his ACL early in 2019. Again, more options than opportunities.
Draft pick: RB Clyde Edwards-Helaire
Replacement: Chris Curry vs. John Emery Jr. vs. Tyrion Davis-Price
Edwards-Helaire was backed up by a trio of freshmen last year, and while none of them really stood out -- they combined for 140 rushes for 668 yards (4.8 per carry) and 19 catches for 157 yards -- they were, after all, freshmen. Davis-Price was the most efficient of the bunch, and Emery was one of the top prospects in the 2019 class. The odds of someone good emerging from this battle are strong.

Alabama
Draft pick: QB Tua Tagovailoa
Replacement: Mac Jones vs. Taulia Tagovailoa vs. Bryce Young
I think this is Jones' job to lose, and I thought that before the elimination of spring practice cut opportunities for Tagovailoa and Young, a blue-chip freshman, to chip away at his lead. Jones did a lot of things awfully well last year after Tua was injured, and he'll still be working with an awfully strong receiving corps.
Draft picks: WRs Jerry Jeudy and WR Henry Ruggs III
Replacements: John Metchie vs. Slade Bolden vs. Tyrell Shavers vs. Chadarius Townsend vs. Thaiu Jones-Bell
The return of DeVonta Smith and Jaylen Waddle means Bama already has two of the most proven offensive playmakers in the SEC. But losing Jeudy and Ruggs means having to replace 117 catches and 1,909 yards, and no other returning WR caught more than four passes last year. That means a wide-open battle. Metchie (Ruggs' backup at the X-receiver spot) and Bolden are sophomores, and Shavers is a junior and former blue-chipper. Townsend is a converted running back, and Jones-Bell is the most touted of a trio of incoming freshmen. When you have a lot of highly regarded options, the odds are good that a couple will come through. But it's not clear who that might be just yet.
Draft pick: OT Jedrick Wills Jr.
Replacement: Evan Neal vs. Tommy Brown vs. Pierce Quick vs. Amari Kight
The return of left tackle Alex Leatherwood means that Bama isn't replacing both All-American tackles, but a youngster will likely replace Willis on the right side. Neal started at left guard last season, Brown is a sophomore who logged 100 snaps, and Quick and Kight are redshirt freshmen. They are all blue-chippers, of course, and Brown was tremendous in his limited opportunities, but it will be hard to avoid a bit of a drop-off in a key pass-protection spot.
Draft pick: S Xavier McKinney
Replacement: Jordan Battle vs. freshmen
All three of last year's starting safeties are gone, so there are no incumbents to ease the stress of losing someone as good as McKinney. That said, Battle put in nearly 400 snaps as McKinney's backup and looked good; he's almost certainly going to be the replacement there if everything at strong safety and nickel is stable. But that stability will depend on either some of last year's lesser-used backups (Daniel Wright, DeMarcco Hellams) or a couple of freshman blue-chippers like Brian Branch and Kristian Story.
Draft pick: CB Trevon Diggs
Replacement: Josh Jobe vs. the field
Jobe is the favorite to line up opposite Patrick Surtain II -- Jobe logged nearly 300 snaps last year and allowed a solid 6.3 adjusted yards per attempt in coverage. He's like half a returning starter. But he's going to have to fend off Jalyn Armour-Davis (also a potential starter at nickel), Ronald Williams Jr. (a juco transfer) and a host of freshmen and sophomores. We don't totally know about quality yet, but the Tide have quantity.

Ohio State
Draft pick: DE Chase Young
Replacement: Jonathon Cooper vs. Zach Harrison vs. a really high bar
For a defensive end, a pressure rate over about 10% on pass-rush attempts is quite good. In the first four games of 2018, Ohio State's Nick Bosa was at 21% before injury. In 2019, despite seemingly facing sextuple-teams late in the year, Young finished at 19%. So who's next? Cooper hit 10% last year before redshirting due to injury, and Harrison finished at 9%, which is solid for a freshman. But can either of these ends, or juniors Tyreke Smith and Tyler Friday, meet the standard that Ohio State ends have set in recent years?
Draft picks: CBs Jeff Okudah and Damon Arnette
Replacements: Cameron Brown vs. Sevyn Banks vs. Marcus Williamson
Safe to say, Shaun Wade will occupy one of the spots left by these two soon-to-be-drafted corners. He put in over 500 snaps last year and produced as many havoc plays (tackles for loss, passes defensed, forced fumbles) as either Okudah or Arnette. But the other spot is up for grabs. Brown and Banks each logged over 160 snaps and allowed under 4 adjusted yards per attempt in limited opportunities, while Williamson was at 81 snaps and 8.3 AY/A. If they all falter, a freshman like Lejond Cavazos could become an option.
Draft pick: RB J.K. Dobbins
Replacement: Master Teague III vs. Trey Sermon vs. Marcus Crowley vs. Steele Chambers
It's possible that all these guys play a role in replacing Dobbins' 2,250 total yards of production (rushing and receiving). Sermon matched Dobbins' efficiency numbers at Oklahoma but wasn't as explosive. Teague was nearly as explosive but less efficient. Crowley and Chambers were dynamite in small samples. There's a bounty of potential here, but Dobbins set a high bar.

Clemson
Draft pick: OLB Isaiah Simmons
Replacement: Mike Jones Jr. vs. Trenton Simpson
Defensive coordinator Brent Venables used Simmons to trademark the modern nickelback/OLB position, but not just anyone will be able to match the 16 tackles for loss, 11 passes defensed and 18 run stuffs Simmons produced. That said, Jones was excellent over about 12 snaps per game. Projected over the same number of snaps, Jones would have had 13.5 TFLs, 5 PDs and 18 run stuffs. Not bad for a redshirt freshman. He'll have to fend off Simpson, a top-100 prospect from Charlotte.
Draft pick: CB A.J. Terrell
Replacement: Mario Goodrich vs. Sheridan Jones vs. Andrew Booth Jr. vs. LeAnthony Williams
Junior Derion Kendrick gives Clemson a sure-thing, No. 1 corner, but someone has to step up and fill the No. 2 role. These four candidates are all sophomores or juniors, and they all saw the field a smidge. Goodrich thrived (3 PDs, -1.17 AY/A), but in a small sample. They'll get first cracks at the job, but a challenge from freshman blue-chipper Fred Davis II looms.
Draft pick: WR Tee Higgins
Replacement: Joe Ngata vs. Cornell Powell vs. Frank Ladson Jr. vs. E.J. Williams
Clemson's receiver recruiting has been absurd in recent years, and while Higgins was maybe the best No. 2 receiver in the country (1,167 yards, 12.8 per target), there are high-end candidates for a spot in the rotation alongside Justyn Ross and Amari Rodgers. Powell is a senior who waited his turn, Ngata and Ladson are blue-chip sophomores who were used on Higgins-esque deeper routes with middling success, and Williams is an incoming all-world freshman. The odds of one of them thriving are high.

Oklahoma
Draft pick: WR CeeDee Lamb
Replacement: Jadon Haselwood vs. Theo Wease vs. Theo Howard vs. Obi Obialo
In Z-receiver Charleston Rambo, the Sooners return at least one proven entity. But who lines up at the X? Haselwood and Wease were the Nos. 1 and 3 receiver prospects in the 2019 class, and they combined for 27 catches, 408 yards and 3 TDs last year. They'll be pushed by two transfers -- UCLA's Howard (51 catches, 677 yards in 2018) and Marshall's Obialo (60 for 749 in 2018 and part of 2019).
Draft pick: LB Kenneth Murray
Replacement: Caleb Kelly vs. DaShaun White
It appears one of two veterans will replace OU's tackles leader. White started on the weak side last year, which Kelly did in 2018 before missing last season with injury. Neither has proven the same level of havoc potential as Murray, however, and this was already a defense that needed to figure out how to disrupt good offenses more. (Whoever doesn't start in the Mike role will probably start at Will.)
Draft pick: QB Jalen Hurts
Replacement: Spencer Rattler vs. Tanner Mordecai
For the first time since 2014, it appears OU will not start a transfer at QB. Mordecai was excellent as a redshirt freshman in mop-up duty, but few prospects have the raw potential that Rattler showed both in high school and in a small 2019 audition. It's safe to say that either will thrive in a Lincoln Riley offense, of course, but is Rattler ready as a redshirt freshman?

Auburn
Draft pick: DT Derrick Brown
Replacement: DaQuan Newkirk vs. Coynis Miller Jr.
It's rare that a tackle leads a team in havoc plays, but Brown's a rare athlete. He leaves big shoes to fill for whoever lines up next to Tyrone Truesdell. While the Tigers have a few players who could play either interior or exterior roles up front, the two most likely options are old-fashioned 300-pounders. Newkirk and Miller combined for about 300 snaps last year, and while they only made 6.5 total tackles, 2.5 of them were for loss.
Draft pick: CB Noah Igbinoghene
Replacement: Marco Domio vs. Nehemiah Pritchett vs. Jaylin Simpson
Auburn must replace both of last year's starting corners, but junior Roger McCreary was basically a starter, too, and performed well enough to assure himself of one spot. The other is less clear. Pritchett (a sophomore) and Simpson (redshirt freshman) saw a little bit of action, but the door is wide open for Domio, a four-star transfer from Blinn College (Cam Newton's juco alma mater).
Draft pick: DE Marlon Davidson
Replacement: Derick Hall vs. Big Kat Bryant vs. Colby Wooden vs. Zykeivous Walker
Davidson had 7.5 sacks last season; the other returning ends on the roster had a combined 3.5. The Tigers have plenty of former blue-chippers to choose from, but none has really played like it yet. Hall and Bryant are the most likely starters, but if they don't take advantage of their incumbency, a redshirt freshman like Wooden or an incoming blue-chipper like Walker could take advantage.

Notre Dame
Draft pick: TE Cole Kmet
Replacement: Tommy Tremble vs. Brock Wright vs. Michael Mayer
Kmet was both a solid receiving threat (57% success rate) and, at 265 pounds, a big blocker. His responsibilities could be divvied out in 2020: Tremble is a 235-pound sophomore who caught 16 passes with a 60% success rate, and Mayer is a 235-pound freshman blue-chipper. Wright, however, was used primarily as an extra blocker (143 snaps, 3 targets) and could be used a lot more in that regard moving forward.
Draft pick: WR Chase Claypool
Replacement: Bennett Skowronek vs. Kevin Austin Jr. vs. Jordan Johnson
None of the three most likely Claypool replacements played for Notre Dame last year. Skowronek is a Northwestern transfer who caught 90 passes in 2017-18, Austin is a former star recruit who missed 2019 due to suspension, and Johnson was the No. 6 receiver prospect in the 2020 class. Skowronek has proven efficient and reliable, but the upside of the other two is hard to ignore.
Draft pick: DE/OLB Julian Okwara
Replacement: Daelin Hayes vs. Isaiah Foskey vs. Ovie Oghoufo vs. Jordan Botelho
The Irish were hit pretty hard by injury at the end position -- Okwara missed the last four games of the year, and Hayes missed the last nine. Hayes could end up as either rush end or as more of a run supporter; where he goes might depend on whether a younger pass-rusher steps up. Foskey didn't do much in a four-game redshirt audition, but the less-touted Oghoufo produced a solid 12.5% pressure rate in 48 pass-rush attempts. A four-star freshman, Botelho could quickly carve out a niche, too.

Georgia
Draft pick: OT Andrew Thomas
Replacement: Jamaree Salyer vs. Xavier Truss vs. Warren McClendon vs. Broderick Jones
While the Georgia interior line is set, the Dawgs have to replace both tackles. Salyer, a junior who logged 200-plus snaps last year and barely missed a block, should have the inside track to one of those roles, but the other starting spot will either go to a barely used redshirt freshman (Truss or McClendon) or Jones, the No. 1 tackle prospect in the 2020 class. Head coach Kirby Smart has proven he will play a true freshman in the trenches if he has to; will Jones be ready for the responsibility of left tackle?
Draft pick: RB D'Andre Swift
Replacement: Zamir White vs. James Cook vs. Kenny McIntosh vs. Kendall Milton
UGA loses both Swift and backup Brian Herrien, and it's hard to even pretend to worry. All four potential replacements are former blue-chippers. On 78 carries, White produced a success rate equal to Swift's (50%), and McIntosh flashed major explosiveness in 25 carries of his own. Milton is an incoming blue-chipper; we'll see if there's a role for him or if he has to wait his turn.

Penn State
Draft pick: DE Yetur Gross-Matos
Replacement: Jayson Oweh vs. Shane Simmons vs. Adisa Isaac
Defensive coordinator Brent Pry has an ace in the hole: Senior end Shaka Toney nearly matched Gross-Matos' pressure rate (11.3% vs. 11.5%) last year. The spot opposite Toney? Unclear. Simmons is a senior who has been in or around the rotation for a while, but both Oweh and Isaac are blue-chip sophomores and, in backup roles, produced 9.2% and 10.1% pressure rates between them.
Draft pick: WR KJ Hamler
Replacement: Daniel George vs. Cam Sullivan-Brown vs. TJ Jones vs. John Dunmore
If Hamler remained in State College, PSU would seemingly have almost everything it needs to perform at or near a top-five level. But his departure means the Nittany Lions have no clear No. 1 receiver. Tight end Pat Freiermuth and slot man Jahan Dotson are handfuls, but between the big-bodied George, the speedy Sullivan-Brown and the two well-regarded redshirt freshmen (Jones and Dunmore), someone needs to step up immediately. This foursome combined for just 17 catches last year.

Oregon
Draft pick: QB Justin Herbert
Replacement: Tyler Shough vs. Anthony Brown
It appeared the battle to succeed Herbert was over, as Shough, who completed 12 of 15 passes for 144 yards and three scores last season, took the first-string reps in the abbreviated spring and did well with them. But then the Ducks scored a commitment from Brown, a Boston College grad transfer who completed 57% of his passes in 2018-19 while showing major run efficiency potential. Shough is a former ESPN 300 prospect and might fend off Brown just fine. But it appears the competition will open back up, at least briefly, in the preseason.