Among the most overlooked aspects of the NFL offseason is player development. We fixate on more tangible occurrences and events: the NFL draft, free agency, trades and other transactions. But the reality for rookies in the NFL is that not all are ready to make a decided impact from Day 1; it makes you appreciate the efforts of players such as Kareem Hunt and Alvin Kamara in 2017 even more.
Some need the chance to grow, with many NFL coaches feeling as though the largest leap in a player's development takes place from his rookie to his second season. With that idea in mind, I've decided to hone in on some players whose fantasy value could ascend in Year 2, looking back on examples of such in 2017 like Carson Wentz and Jared Goff at quarterback or Kenyan Drake at running back.
Corey Davis, WR, Tennessee Titans

It became a weekly tradition for me to anticipate the Davis breakout game last season, as the immensely talented wideout showed flashes almost immediately: He led the Titans with 10 Week 1 targets. Injuries, inconsistent quarterback play and room to grow kept Davis from catapulting during the regular season, but he reminded us in the playoffs of what was to come. He scored in each of the Titans' postseason games, carrying a 23.1 percent target share during those two outings. He passes the eye test, has the raw physical tools (he was the fifth overall pick for a reason) and enters the year healthy. Watch out.
Joe Mixon, RB, Cincinnati Bengals

Mixon's average 2017 was overshadowed by the standout years for Hunt, Kamara and others, but there were a few positives to take away from it. It starts with the fact that he's the unquestioned starter and Jeremy Hill is no longer in the mix (Hill had a role in Cincinnati early on in 2017). Giovani Bernard averaged a career-low 6.6 attempts per game, with Mixon toting the rock 17 or more times on five occasions. Cincy wants him to be the workhorse and he's also a factor in the passing game, hauling in 88.2 percent of his targets. Mixon's talents are undeniable, despite what he showed last season. The question that looms largest is whether a retooled offensive line will give him space to run (he ranked 41st out of 47 qualified backs in yards before first contact per carry last year). If so, he's got top-15 upside.
Patrick Mahomes, QB, Kansas City Chiefs

Mahomes isn't quite a Ben Simmons-level rookie this season, but he's got just one NFL game to his name thus far. But here's what we know: He showed well in that Week 17 start and has a unique skill set that includes an oversized arm. The Chiefs' pass catchers happen to align with said arm strength, as 14 percent of Tyreek Hill's career catches have gone for over 30 yards (compared with an NFL average of just 7.2 percent since the start of 2016), while newcomer Sammy Watkins has a 14.74 career air yards per target, sixth highest among 174 qualifying players since the 2014 season began. Mahomes will endure some peaks and valleys, but playing in an offense that will need to score plenty (the defense has some holes), he should have some robust Sundays.
Tarik Cohen, RB, Chicago Bears

A hot start in 2017 introduced the world to Cohen, though his production leveled off quickly. The Bears' new offense -- orchestrated by head coach Matt Nagy and coordinator Mark Helfrich -- should see a spike in creativity and output with the development of Mitchell Trubisky (more on that soon) and an improved arsenal of weapons. While I don't believe Cohen will ever be a super high-volume player -- he's pint-sized and needs to be managed in that regard -- he's such a dynamic pass catcher that Nagy feels bound to scheme him double-digit touches per game. He had 53 catches last season and should see an overall usage increase. Watch out for big plays from Cohen.
David Njoku, TE, Cleveland Browns

This column led with the notion that players have often seen their largest leap between Years 1 and 2. For Njoku, part of what held him back in Year 1 was the sheer volume of targets -- just 60 in total. Yes, Cleveland has a more complete receiving corps this year when players like Jarvis Landry and Josh Gordon figure to be featured, but Njoku -- a truly freakish athlete -- has a chance to make a splash in the red zone.
Aaron Jones, RB, Green Bay Packers

There's a case to be made for also including Jones' teammate, Jamaal Williams, but let's focus on Jones for a second. He'll serve a two-game suspension to begin the season, which means he's likely to be available late in drafts as a flier. The Packers had a carousel of backs last season and could again in 2018, but during the four-week stretch in which Jones got the chance to be "the guy," he flourished. He was RB8 from Weeks 4-7, averaging 5.58 yards per carry. Despite close to half as many carries as Williams, Jones had six runs of 20-plus yards, while Williams had just one. This is a talent hedge -- Jones could emerge as Green Bay's best back.
Mitchell Trubisky, QB, Chicago Bears

One of the trendiest breakout players in 2018, Trubisky could see a Jared Goff-like ascension. Entering his second season, Trubisky -- like Goff a year ago -- has a new, offensive-minded head coach and a wildly improved supporting cast: Allen Robinson, Trey Burton, Anthony Miller and Taylor Gabriel headline the newcomers. Trubisky got little in the way of help last season, but he improved down the stretch, posting a 67.1 completion percentage in Weeks 13-17, up from 52.8 percent prior to that. He's an excellent athlete who accrued 41 rushes last season, something that helps raise his floor. In two-quarterback leagues, he's certainly on the radar, with sleeper potential across all formats.
Dede Westbrook, WR, Jacksonville Jaguars

Westbrook returned from the injured reserve list to make a prominent mark on the Jacksonville offense, seeing a target on 22 percent of his routes run, 25th-best in the NFL. That suggests that volume should work in his favor, albeit in a run-heavy scheme. But looking at Jacksonville's receiver depth chart, it's at least plausible that Westbrook will lead the team in targets, as he had at least seven in five of the seven regular-season games he played. He's so explosive (he had a 20-plus-yard catch in four of seven games played) and now healthy ... look for Westbrook to make the leap.
George Kittle, TE, San Francisco 49ers

Another promising second-year tight end, Kittle has a chance to emerge as a security blanket in the middle of the field for Jimmy Garoppolo. He posted 100 yards in the final game of the 2017 regular season and -- like the rest of his teammates -- appeared to benefit from having Jimmy G. under center. While Garoppolo was sharp for the 49ers in five games as a starter, he threw just six touchdown passes. That total figures to go up and so too will the production of his pass catchers.
D'Onta Foreman, RB, Houston Texans

A massive caveat to note: Foreman is coming back from an Achilles tear that could limit his availability to begin the season. But if he returns to form, it stands to reason his role could inflate, as Lamar Miller's yards per carry have dipped during each of the past four seasons and he failed to hit the 75-yard mark in a game once in 2017 despite 238 carries. Foreman has the chance to excel at yards after contract with his imposing frame and speed.
Taywan Taylor, WR, Tennessee Titans

We pounded the table for his teammate Davis to lead this column, but now let's give some love to Taylor. He ran a route on 73.5 percent of his snaps last season, albeit under a different coaching staff. Most of this is a talent-based proclamation: Taylor was an exciting add via the draft from Western Kentucky last year and I'm confident he'll see an uptick in usage.
Marlon Mack, RB, Indianapolis Colts

Mack, coming off shoulder surgery, is fighting for carries in a now-crowded backfield. I've got him on this list because the dude is explosive, posting a carry of 10-plus yards in nine of 14 games in 2017 despite having just one with more than 11 carries. All Colts running backs classify as dice rolls for now, with Mack in the mix.
Mike Williams, WR, Los Angeles Chargers

The intrigue with Williams starts with his ridiculous college career at Clemson and physically dominant stature (he's all of 6-foot-4 and 220 pounds). An injury set his season back before it even began last year, but he's the ideal lottery ticket late in the draft. The presumptive No. 2 target in the passing game in L.A., Hunter Henry, is out for the season due to an ACL tear. Keenan Allen needs someone to ride side car among the wideouts and that's where Williams has a chance to make an impact. If he can supplant Tyrell Williams on the depth chart, a major boost in production will follow, as there are yards to be had in L.A. ... Philip Rivers has thrown for 4,200 yards or more in eight of his past nine seasons.
Kenny Golladay, WR, Detroit Lions

Golladay was a preseason standout for the Lions in 2017, immediately generating interest in the fantasy world. He showed that promise during the regular season, albeit in a limited role, posting 28 catches for 477 yards and three touchdowns. He averaged 14.45 air yards per target, a number that floats in the real estate of deep threats like Martavis Bryant and Kenny Stills, suggesting big plays will continue for Golladay despite the fact that he's the clear No. 3 receiver in Detroit's offense. His best value might be as insurance to someone with Marvin Jones Jr. or Golden Tate on his or her roster, as there is upside.
John Ross, WR, Cincinnati Bengals

Perhaps best described as the ultimate flier, there is nowhere for Ross to go but up. He had zero catches last season. Zilch. But let's not forget he set the combine record for the 40-yard dash and Cincinnati is looking for passing-game answers to complement A.J. Green. Ross is bound to make strides, the question is just how far -- we're banking on a robust role.