This is an interesting phenomenon, though one that (for various reasons) has gone largely unnoticed: There were seven (or eight, if you’re feeling generous) regular big-league shortstops in 2015 who were born in the seven months between early September 1989 and late March 1990. I’ve been tracking their progress for years, wondering when one or another edged ahead of the field as the most valuable, trying to gauge their relative market standings. It was always hard to tell, though, because for each player, development has been anything but linear, and their values have seemed to be very volatile. The group even flexed in size and membership over the years, reaching (probably) its maximum size in 2015.

This winter, we finally got a little clarity (though only a little). Four of these shortstops changed teams this winter, all via trade. At least two permanently moved on from being shortstops. From here on out, the careers of these seven (or eight) players with so much in common might seem thoroughly disparate, even though (perhaps most remarkably, of all the interesting things about them) their paths to this point in their careers have often crossed—and in some cases, have even altered one another. Thus, I want to take a moment to consider their respective situations, weigh them against each other, and revel in the entropy that defines baseball, an entropy this group embodies as well as anyone.

Andrelton Simmons
It’s not clear what Simmons is at the plate, even now. The power he flashed in 2013 is all but gone, but he’s solidified his excellent contact skills, which seems to ensure that he’ll never (or at least not anytime soon) be much worse than an average shortstop at bat. Couple that offensive profile with the irrefutable preeminence of his glove (at the second-most valuable defensive position on the diamond), and you have a bulletproof first-division stud.

That’s how Simmons was treated this winter. The Braves traded Simmons to the Angels, and although they were trading a player with five years left on his contract and $53 million owed to him, they were able to extract both Erick Aybar (who should be a flippable asset for them at this year’s trade deadline) and Sean Newcomb, whom we named the 32nd-best prospect, 11th-best pitching prospect, and fourth-best left-handed pitching prospect in baseball last week. Even after that, the Angels threw in enough cash to cover the difference between Aybar’s and Simmons’ 2016 salaries, and uneven (but ultimately interesting) pitching prospect Chris Ellis. The Angels had to back up the truck for Simmons, suggesting that even though he’s past the stage of his career during which he was especially cheap, and even though his glove-heavy skill set figures to age a bit early, he’s considered exceptionally valuable by big-league decision makers.

In Simmons, we can see how much teams like the security of an elite skill. As much and as unpredictably as Simmons has changed as a hitter during his career, the Braves didn’t wait to see what kind of offensive asset he might be before locking him up on a long-term deal. A year before he had any hope of reaching arbitration, the team guaranteed him $58 million on a seven-year deal, the richest contract (by annual average value) that any club had ever given to a player at his service-time level up to that point. Having a bundle of tools and a broad skill set is nice, but Simmons got paid big bucks for his one dimension of dominance.

Brad Miller
Only circumstance pushed Simmons out of Atlanta. There was no question that the organization was dedicated to him, nor that they liked what he was doing for them; he just didn’t fit the direction of the franchise anymore. By contrast, Miller left the Mariners after four and a half years (first as a well-regarded prospect, then a starting shortstop, then a utility man) mostly because the team seemed neither sure of what he is, nor inclined to wait any longer to find out.

It’s hard to suss out a specific valuation of Miller, based on the deal of which he was a part, because multiple pieces flowed in each direction. It’s probably fair, though, to call Danny Farquhar and Logan Morrison a hair more valuable than Boog Powell and C.J. Riefenhauser, and if you accept that, then Miller (with four years of team control left, and due less than $1 million in 2016) netted Seattle five years of Nate Karns (a starter roughly two years older but a year further from free agency), less the value gap between the pairs of spare parts. Karns is solid and has more promise than most people think; he could well be a durable, mid- or late-rotation starter for the balance of his team control. In other words, while not as sexy or as valuable as the package the Braves got back for Simmons, the return for Miller suggests that he retains significant market value. Unfortunately, for reasons both good and bad, he didn’t retain much value to the Mariners.

Ruben Tejada
Add this winter to the long list of turbulent, difficult times Tejada has experienced in his six seasons with the Mets. The stats have always liked Tejada a little better than the scouts, and considerably better than the sports-talk radio hosts and columnists and meatball fans who make up so much of the New York baseball echo chamber. In four of the last five seasons, WARP has estimated Tejada to be worth between 1.9 and 2.9 wins, thanks to roughly average defense at short, and thanks to much better control of the strike zone than most people realize. With a career OBP of .330, Tejada hardly blows you away, but shortstops have averaged a .311 OBP over the course of his career. He has a career walk rate of 8.6 percent, and a career strikeout rate of 15.0 percent. Of course, he hits for no power whatsoever, and his glove is ordinary, but Tejada is a credit to a lineup, a bottom-of-the-order guy who can get on base.

Injuries and faltering trust in Tejada on the part of Mets management have stopped him from finding a real home in the New York lineup, though. Even if he can recover fully from the broken leg he suffered in the playoffs last year, he’ll have Asdrubal Cabrera and Wilmer Flores in front of him on the depth chart. It’s a good bet that the Mets’ actions this year serve as an indirect but clear indicator of their intentions for Tejada, and unfortunately, he looks like he might run out of chances to be an everyday shortstop before he gets in a really good, healthy year.

Jose Iglesias
One of the few peaceful winters among this Gang of (Seven or) Eight went to Iglesias, who had a fine season in 2015. He’s well regarded, and he’d be even more well regarded if this were 1986. He makes contact, and though that’s his only real offensive skill (he hits everything on the ground, never hits the ball hard, and rarely walks), it’s worked well for him so far. He won’t even reach 1,000 career plate appearances unless and until he plays about four healthy weeks this spring, but he feels like an established regular.

It’s not totally clear that he should be. In fact, one could make the case that the Tigers erred by using Eugenio Suarez as a trade chip last winter, instead of keeping him and giving him the chance to win their shortstop gig. Suarez is a better hitter, though he gets there in a less appealing way (lower average, more power), and while Iglesias is almost certainly a better fielder, the numbers don’t support the scouting reports we all heard about his glove all that well. He’s capable of highlight-reel plays, but doesn’t seem to have consistently wide range. Few are the teams who will ever replace their .300-hitting shortstop, and Iglesias got a vote of confidence, in that the reloading Tigers never seemed to even consider moving on from him, even as they revamped their outfield and their pitching staff. Still, it might be that they should consider that, because Iglesias has reached the age at which players basically are who they appear to be, and he appears to be a second-division shortstop.

Tim Beckham
None of these players entered professional baseball with as high a pedigree as Beckham, who was the top overall pick of the 2008 Draft (not that everyone thought he was truly the top overall talent). Since then, though, Beckham has slowly proved himself not to be a viable big-league player. He flashed promise half a decade ago, in the lower levels of the minors, but the .254 TAv he scraped out in 223 plate appearances for the Rays last year about encapsulates the last several seasons of his career. It was enough to convince the Rays—who could have held shortstop for him for one more year, giving him a chance to prove himself or simply signing a low-level free agent like Alexei Ramirez—to elect to pursue Miller instead. This winter (and the Miller move, in particular) formalized, and likely made permanent, Beckham’s disenfranchisement. He never really got a shot in the big leagues, but then, he never really earned one.

Didi Gregorius
This is, ostensibly, a group of young shortstops. That’s really what has made them interesting up to this point. It’s funny, then, that collectively, they feel both as though they have been around forever, and as though they’re quite old (for being so ill-established). This is the way in which baseball cruelly reminds us all that we’re older than we think, that we’re running out of time even while we feel young, and that everything glowing about us—enthusiasm, passion, energy, and most especially, celebrity—fades steadily and inexorably, until the lights go out.

I mention this because (did you know?) 2015 was the first season in which Gregorius qualified for the batting title. At age 25, Gregorius was playing for his third team, was responsible for taking the torch from the very player to whom he was infamously compared, by a GM who had traded for him two years ago, and who had recently been fired for moves (and quotes) like that one, and whose successor had made trading Gregorius one of his first priorities. He responded by posting 2.2 WARP in 155 games, running the bases well, fielding his position well, and meeting the (low) offensive standard of his position.

That should be an encouraging season. I can’t shake the feeling that being a two-win shortstop at age 25, after bouncing around like Gregorius, should be a good sign. It is a good sign, of course, in that it demonstrates Gregorius’s ability to be a two-win shortstop in the big leagues, and in that a two-win shortstop is a fine thing to have on hand. The problem: there’s absolutely nothing whatsoever to dream on here. Gregorius didn’t find a new outlet for his speed, didn’t find that he could reach the short porch in right field at Yankee Stadium, didn’t thrive at a new level in a more progressive franchise’s more evolved defensive setup, didn’t suddenly make contact at an exceptional rate, didn’t develop even that late-in-the-order kind of plate discipline where pitchers are okay with walking you and you learn to use that against them. Gregorius’ skill set is as bland and unappealing as the personality of the shortstop (whose skill set was, however maligned at times, elite and thrilling) he replaced. PECOTA looked at his season, which was certainly not a breakout but was certainly marked progress, and shrugged: It pegs him for 2.1 WARP and a .248 TAv this coming season. In baseball, it’s perfectly possible to have achieved a modest level of success by age 25, but to have no measurable potential to move any further up the ladder.

But wait! PECOTA’s top comp for Gregorius is Brandon Crawford, and Crawford, come to think of it, was just getting his land legs at 25, too, and didn’t really give any indication of the offensive force he would become until he was 27. He was always a better defender at the position than Gregorius will ever be, but there he is, at the top of the comp list for Gregorius, polishing his Silver Slugger award with newspaper clippings from the day he signed his six-year, $75 million extension. There will probably not be another Crawford in the next 10 years, and if there is, Gregorius is unlikely to be that guy. Yet, there’s always something like this, to seduce you into believing in a player who doesn’t provide much cause for that confidence. This game, man.

Nick Ahmed
Gregorius is in New York, in part, because the Diamondbacks wanted to give Ahmed his shot to prove himself a credible big-league regular. He did so, excelling defensively (indeed, he’s probably the second-best defender in the group, and it’s no discredit to be second to Simmons). On the other hand, he, too, proved that he’s never going to hit like a big-league regular. His .236 TAv was the 14th-worst of the 176 batters who had at least 450 plate appearances last season. He ran the bases very well, and his glove really might keep him afloat (PECOTA projects 2.0 WARP for him this season, on the strength of an excellent defensive projection). Still, there’s more than one reason that the Braves traded Ahmed to Arizona in the Justin Upton deal three years ago. One reason is that they had Simmons. The rest of the reasons are all of the rallies Ahmed’s bat kills in a National League lineup, plus the fact that the Braves believe WAR (and WARP, presumably) overvalues defense, anyway. Clearly, despite Ahmed’s defensible work as a defense-first shortstop, the Diamondbacks weren’t satisfied, either.

Jean Segura
We can tell the Diamondbacks weren’t satisfied, because they traded for Segura on Saturday. Segura had an even worse TAv than did Ahmed in 2015, at .217, though some stats say he had an even better defensive season than did Ahmed, too. Now the Diamondbacks, like the Rays, own two of these eight players. It doesn’t seem profitable to do that, but then again, Arizona would have had to play Chris Owings (an even worse hitter in 2015 than either Ahmed or Segura, and not nearly as good a defender) on a regular basis if they hadn’t done this.

Still, even if you believe that one or both will improve at the plate going forward, neither Ahmed nor Segura is a positive addition to a lineup, and neither seems likely to retain any significant value if they aren’t playing shortstop. Across the board, so far, there seems to be a much higher correlation between the acquisition cost teams are paying and the defensive value of the players they’re acquiring than between that cost and the offensive skill sets of the players in question. That’s probably a mistake; these teams should be putting more emphasis on finding guys who can hit. Then again, maybe that’s why these players seem to pass so often through the hands of the same clubs. It could be a matter of philosophy.

Starlin Castro
That Simmons and Castro are the bookends of the group by age is fitting. They stand at opposite ends of the spectrum of offense and defense: Castro might be the worst defender in this bunch, though he looked good after moving to second base last season, but he might also be the best hitter in the bunch. Of everyone in the group, Castro’s value has seemed to move the most, and the most frequently, over the years. He’s been in the majors far longer, or at least has seen far more action, than any of the others. Just when we seemed to have a handle on who he was as a player (and especially as a hitter), though, he would shift again. As recently as the trade deadline, he seemed headed for a season that would permanently derail his career and make the Cubs look silly for having extended him on a seven-year deal prior to 2013. Then, after moving to second, he somehow transformed as a hitter, and had the best stretch of his entire career: He batted .372/.395/.646 over his final 120 plate appearances during the regular season, and hit well in the postseason, despite ugly stats. (He had unbelievably bad batted-ball luck, leading the Cubs in average exit velocity but sporting a .156 BABIP, and he fanned just once in 35 PA.)

For Castro, who is still owed at least $40.4 million over four years, the Cubs got Adam Warren, an older but talented and potentially ascendant swingman. It’s remarkably similar to what the Mariners got for Miller, even though he offered no more team control than does Castro and will probably cost less over those seasons. In other words, Castro’s contract appears to have been considered value-neutral, at least by the Yankees—who become the third team in baseball currently in possession of two of these players.

It’s unlikely that Castro holds on to those wild improvements from late last season. It’s not impossible, though, and certainly, his brutal first half looks a little more like an aberration in light of that late charge. It also helps that New York can slot him in at second without controversy; Castro’s body and his stats both indicate that he’s better off there.


In hindsight, these players hewed pretty closely to one another in terms of overall value throughout their early 20s. They’re mostly slightly below-average players, worth between one and two wins when they can get a full season of playing time. They all get to their value somewhat differently, though, and it’s remarkable the way those small differences (or the big differences of good and bad luck, good and bad makeup, good and bad player development on the part of the teams who brought them along) have sent them in such different directions.

I asked Sam Miller to rank Castro, Gregorius, Segura, Simmons, and Tejada, for both the short and the long term, in a May 2013 chat. Sam’s answer:

Short: Castro, Segura, Gregorius, Simmons, Tejada
Long: Castro, Segura, Simmons, Gregorius, Tejada

For the record, I wrote down my own answer to the question at the time:

Short: Segura, Castro, Simmons, Tejada, Gregorius
Long: Castro, Segura, Simmons, Tejada, Gregorius

I asked the same of other people on Twitter and in other chats throughout that year, and Castro always led the way, usually with Segura right behind him. It would seem that we all underestimated Simmons, jumped to conclusions a bit on Segura, and felt a little too comfortable with Castro’s track record, absent evidence of a breakout from him. I was too hard on Gregorius, and too soft on Tejada. Sam nailed that. Most interestingly, I tweeted as recently as August 11th that Castro might have fallen so far as to become the least valuable player in the set, and yet, after the winter’s moves, it looks like he fits comfortably into the second tier of value within the group, behind Simmons but right alongside Miller and Iglesias. For now, anyway.

By no means did these eight players (or even the five I was focused on two-plus years ago) ever have identical profiles. Still, given their ages, their positions, their general experience level and their overall values, they could be seen to share a very similar starting point. To watch them fill in so many different boxes on the possibility matrix in the short time since they all left that point is a reminder of just how little certainty we can claim whenever we project young players’ development.

Thank you for reading

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I understand that PECOTA has been under the gun recently for some rather bizarre evaluations, like the Royals of the last three years, but if PECOTA actually compares Gregorius to Crawford it is time to reprogram it or retire it.