While a lot of the focus of discussions this time of year is on which prospects contending teams should trade for which stars, quite often simply using their own top-performing prospect is a superior choice for a ballclub in win-now mode.
Nine players called up since Tax Day (April 15, for those outside the U.S.) already have been worth at least a half-win's worth of WAR. Some of these players are having real pennant race impacts so far: Gleyber Torres, Austin Meadows, Ronald Acuna Jr., Jaime Barria, Seranthony Dominguez and Nick Kingham are all making a difference on teams that have been competitive. These aren't players getting opportunities with rebuilding teams just throwing stuff at the wall and seeing what sticks. Plus, Juan Soto! He just missed my 0.5 WAR cutoff, but the kid is hitting .312/.404/.571, so we have to mention him.
Teams are far from being out of homegrown talent to lean on, whether they're contending or pretending -- or just want to play spoiler. Whether it's a top prospect or a lower-ceiling player in the high minors who can make a short-term impact, more reinforcements are on the way. With each of these players, these are their projected performance at the MLB level if they were called up today; let's hope they get the opportunity to make good on them soon.
3B Vladimir Guerrero Jr., Toronto Blue Jays
The Vladimirovich wasn't arriving quietly, destroying the Eastern League to the tune of a .407/.457/.667 triple-slash line with 11 homers when a knee injury gave Double-A pitchers an opportunity to sleep peacefully for the next four weeks while he's out. Before that setback shelved Vladi Jr. for the rest of June, the official explanation for his continued presence in the minors was of the "improve his defense at third" variety, given that his glove isn't as far along as his bat.
But the point of calling up Vlad once he has recovered is not just to get him some major league seasoning but also to help the team as soon as possible. After a 9-19 May, the Blue Jays drifted out of obvious contention, and at 33-38, they need to add a lot of wins, given that they're currently 13 games behind in the race for the American League's second wild card. Plus, they aren't playing in one of the weak divisions, so the wild card is their only real ticket to October.
If the Jays aren't yet willing to throw in the towel on the 2018 season, then getting any win from wherever they can is crucial if they want to overcome their odds against September relevance. Kendrys Morales, the primary designated hitter, has a 75 OPS+ entering Sunday. If you really want to win now, do everything you can to win now. If it fails -- as is likely -- there's nothing keeping you from sending Vlad back down to Triple-A to work on third base and to concentrate on that over the winter.
ZiPS projection for the rest of 2018:
INF Nick Senzel, Cincinnati Reds
Senzel won't get the Reds back into a race from which their 7-24 start effectively eliminated them, but with four teams in the National League Central in contention (even the fourth-place Pirates are just 3½ games behind in the race for the second NL wild card), the Reds have the opportunity to play spoiler -- and not just to play spoiler but also to start looking at their future configuration. Senzel's future position isn't set in stone: The Reds just gave him his first professional start at shortstop in Triple-A after testing him there in spring training.
It also might be best for the long-term health of the organization if Senzel comes up and pushes the team to trade Scooter Gennett. Admittedly, Gennett is having a magical season, but he also is just over a year from free agency, and the Reds have a lot of long-term team needs that they aren't close to meeting with their current base of talent. By waiting forever, circumstances led to the Reds' selling low on Todd Frazier and Aroldis Chapman and ending up with nothing for Zack Cozart's breakout, not even a compensation draft pick. Gennett's free-agent contract will cover years into his 30s, which is not something the Reds should be signing up for, given where the team is.
ZiPS projection for the rest of 2018: .273/.335/.432, 20 home runs
RHP Enyel De Los Santos, Philadelphia Phillies
The Phillies aren't truly suffering for starting pitching right now. Vince Velasquez's ERA might be a bit worse than the team would like, but his FIP is well below 4.00, so it's perhaps not the most obvious fit to throw De Los Santos into the rotation. But why not swipe a page from Earl Weaver, who loved to break in starting pitchers with a stint in the pen, and add some depth there simultaneously?
De Los Santos has worked out marvelously since he was acquired for a year of Freddy Galvis, but with a 1.47 ERA and 76 strikeouts in 73⅓ innings in his first taste of Triple-A, at this point is he really being challenged in the minors? ZiPS projects the team's bullpen to be among the bottom relief crews for contenders.
ZiPS projection for the rest of 2018: 4.32 ERA, 8.0 K/9 as a starter, 3.45 ERA in relief
OF Raimel Tapia, Colorado Rockies
There's little question that the Rockies' management of the hitting side of the defensive spectrum (first base and the outfield corners) has been a mess for a long time. Ian Desmond is somehow on a 35-homer, minus-2.0 WAR pace, and while the lines of Gerardo Parra and Carlos Gonzalez are superficially better, posting an OPS under .750 while playing half of your games at Coors Field is replacement-level offense.
There's no guarantee that Tapia will be even a league-average player, but he gives the Rockies, last in MLB in OPS+, some actual upside. Tapia hasn't torn up the PCL, but he is young and has raw talent, and if the Rockies want to show a particular strength of spine, they could put Charlie Blackmon into a corner, where he probably should be, given his defense this year.
ZiPS projection for the rest of 2018: .289/.320/.445, with five triples, six homers and 17 stolen bases
2B Keston Hiura, Milwaukee Brewers
Just a year since the 2017 draft, when Hiura joined the organization, the best-projected Brewers second baseman for the rest of the 2018 season isn't Jonathan Villar or Brad Miller, it's Keston Hiura. He started the season hitting .320/.382/.529 in high-A and stands at .382/.433/.545 since being promoted to Double-A. ZiPS isn't usually this exuberant about players with little time in the high minors, so I tend to listen a bit more when there's this level of computational ebullience.
Plus, with Orlando Arcia being a disaster for the Brewers this year, both Villar and Miller project better than Arcia at short, even with below-average defense. I expected a lot more from Arcia by this point of his career, but the Brewers are in a real pennant race against at least two teams that have significant financial heft. They will need to save any trades for positions at which they have no good fallback options. Hernan Perez is a perfectly adequate utility player, but fortune favors the bold.
ZiPS projection for the rest of 2018: .271/.325/.435 with seven home runs
SS Adalberto Mondesi, Kansas City Royals
I'm going to cheat slightly here, as Mondesi was called up Sunday morning -- after I had put him in this piece for Monday! But given that Mondesi hasn't played yet and is one of the more interesting players to project and that the team's situation is unchanged since Saturday, I'm going to go with it.
There's no arguing with the fact that Mondesi's play in the majors has been a disaster so far -- a .181/.226/.271 career line, a whole win below replacement level in just 209 MLB plate appearances. But he debuted the day before his 19th birthday and has done as much as he could in the minors since then. After a .305/.340/.539 line for Omaha last year, he should have been handed the shortstop job as soon as he was healthy. His .250/.295/.492 line isn't eye-popping this year, but he has 16 extra-base hits, including three triples and five homers. Plus, he is still just a 22-year-old shortstop, so it's OK that he doesn't have a 1.000 OPS in the PCL.
At this point, the Royals need to move beyond Alcides Escobar. Yes, he's one of the last remaining parts of the team that won the 2015 World Series, but he does nothing for the team at this point. It's time to stop trying to play Escobar 162 games a year and start not playing him 162 games a year.
ZiPS projection for the rest of 2018: .239/.280/.430, with four triples, nine home runs and 18 stolen bases
OF Kyle Tucker, Houston Astros
Houston is not exactly a team begging for help, but 2018 has been much less of a cakewalk in the AL West than the 2017 season was. Yes, the Mariners are likely to regress heavily, given how much of their success has been in one-run games, something that has been nearly impossible to sustain long term in MLB history. But the Mariners are near first place right now, and there's no MLB official who takes away lucky wins.
Houston has been playing it by ear all season as far as who's in the lineup playing left field, but Tucker is young and he is hitting well at Triple-A, and ZiPS projects him as the best option to simply plug and play in left.
ZiPS projection for the rest of 2018: .253/.315/.470 with 12 homers
RHP Nick Kingham, Pittsburgh Pirates
It's absurd that Kingham is even on this list. At the time of his demotion, Kingham had the best strikeout rate, the second-best walk rate and the second-best ERA of the six pitchers the Pirates had started in 2018. Even if you don't start him, he'd do more to win games for the Pirates in the bullpen than either Michael Feliz or Tyler Glasnow is right now.
ZiPS projection for the rest of 2018: 4.11 ERA and 7.2 K/9 as a starter, 3.35 ERA as a reliever