In December, the St. Louis Cardinals acquired Miami Marlins left fielder Marcell Ozuna with hopes that he could maintain his high level of performance from 2017 over the next two seasons in St. Louis. While some hedged their bets, declaring that Ozuna could be merely good or very good rather than a megastar and still be worth the cost of Sandy Alcantara, Magneuris Sierra, Zac Gallen, and Daniel Castano which the Cardinals paid to acquire him, MLB Network came right out and declared Marcell Ozuna the best left fielder in baseball.
On the left field episode of Top 10 Right Now, Ozuna ranked ahead of Yoenis Cespedes and Justin Upton according to The Shredder, a formula of player evaluation used by the network to compile the official player rankings. MLB.com’s Mike Petriello, who unlike The Shredder is not beholden to a mathematical formula if the results do not make sense, concurs with Ozuna at one, flipping Upton and Cespedes to round out the top three.
By 2017 results, Ozuna is certainly deserving of the honor. By Baseball Reference Wins Above Replacement, among players with at least 50% of their games played in left field, Ozuna ranked second. First place is his now-teammate Tommy Pham, who is slotted to play in center field in 2018 and is no longer a candidate for “top left fielder” lists. By FanGraphs Wins Above Replacement, Ozuna ranked second (not counting Tommy Pham) to Justin Upton. Ozuna held a minor lead over Upton at the plate (a 142 wRC+ in 679 plate appearances, to a 137 wRC+ in 635 plate appearances) and in the field (while Ozuna’s defensive statistics were not quite as illustrious as his Gold Glove win might imply, his 3.4 runs saved above average by Ultimate Zone Rating did surpass the 2.1 runs saved by Upton), while Upton held an edge on the bases, stealing 14 bases to Ozuna’s one and accumulating 9.4 more runs by FanGraphs’s measure.
Yoenis Cespedes has a track record mostly comparable to that of Ozuna and Upton, though in 2017, the Mets outfielder made just 321 plate appearances in 81 games. At a 131 wRC+, he was a tick below Ozuna and Upton, though not so far off the pace that he does not merit a place in the conversation, but at what point do durability concerns became a factor? It’s hard to say, but a player missing half the season due to injuries is impossible to classify as a good thing.
Marcell Ozuna in 2016 was not nearly the player he was in 2017, though Justin Upton was worse, fielding poorly and not being enough above-average at the plate (104 wRC+) to be an above-average player on the whole. At 3.2 fWAR, Cespedes was tops among the group, though he was distantly behind the other two in 2017.
To a degree, the sample size used to determine the best when looking at past performance is a matter of risk aversion. The error bars are a bit further spread out in smaller, more recent samples. If, say, a player came out of nowhere to be an MVP candidate (New York Yankees right fielder Aaron Judge, though probably too much of a prospect to be considered “out of nowhere”, is a decent approximation), he might regress substantially but he would also be a stronger bet to repeat his 2017 performance than a consistent four or five win player would be. And if you were looking for a four of five win player, the guy with the track record is the safer bet. Here is how the three left fielders stack up by FanGraphs Wins Above Replacement according to various sample sizes.
2017: Upton 5.0, Ozuna 4.8, Cespedes 1.6
2016-2017: Ozuna 7.4, Upton 6.3, Cespedes 4.8
2015-2017: Cespedes 11.5, Upton 9.9, Ozuna 8.6
2014-2017: Cespedes 14.8, Upton 13.8, Ozuna 12.5
The results here are somewhat dispersed, but it’s worth pointing out that this list is meant to predict 2018 rather than reflect 2017 or some other sample size. Justin Upton is 30 and will turn 31 in August. Yoenis Cespedes is 32. Meanwhile, Marcell Ozuna is just 27. Upton and Cespedes are, by normal aging curves, slightly past their prime—they should be relatively fine, but subject to moderate decline. Ozuna is just now entering his prime. Projection systems reflect this.
Steamer: Ozuna 3.6, Cespedes 2.8, Upton 2.1
Depth Charts: Ozuna 3.8, Cespedes 3.0, Upton 2.3
Projection systems are perhaps underrating the relevance of how good Justin Upton was last year following the trade which sent him from the Detroit Tigers to the Los Angeles Angels (with whom he will play in 2018). And perhaps some left fielders beyond the three Mike Petriello refers to as “the big three” have more upside—Philadelphia Phillies rookie Rhys Hoskins was beyond fantastic in 2017, but in just 212 plate appearances. Cases can be made for other players, though Ozuna is certainly a credible pick.
With that said, the best left fielder in baseball is actually Mike Trout. Of course, Mike Trout is not expected to regularly play left field for the Los Angeles Angels this season—that honor will go to Justin Upton. But if Trout moved to left field, rather than the center field position he occupies because he’s the best defensive center fielder among the starters on his team, he would instantly be tops in the league. The best offensive left field season by someone other than Trout since Trout’s rookie year of 2012 came courtesy of Ryan Braun, who posted a 159 wRC+ in 2012. Trout posted a 167 wRC+ in the worst offensive season of his career.
Mike Trout is, I’m relatively confident in saying, the best left fielder, center fielder, right fielder, and designated hitter in baseball. You might even be able to talk me into first base, a position Trout has never played at the Major League level, though Joey Votto is a really good hitter and also, um, an actual first baseman. Trout is an extreme example, but left field is a position where numerous non-left fielders could play. Almost any center fielder would be above-average in left, most right fielders would be fine to play left field, many (not all) first basemen could at least fake it in left if that were required of them, and so on.
Which is all to say that categorizing Marcell Ozuna as the best left fielder in the game is different than categorizing somebody as the best catcher in the game, or even the best center fielder in the game, spots where players from other positions would be substantially worse defensively if moved to it—Ozuna’s is a position which commands heavy offensive production, and if a great offensive player can play a more valuable defensive position, he will usually find himself there. It takes a truly elite bat (see: Barry Bonds) to be the best player in baseball at the position. With that said, left field is still a Major League Baseball position and being the best at the position is still an accomplishment worth celebrating, and Marcell Ozuna may very well be the best at the position.