But over the past two months, the Belli-vs.-Yeli narrative has been compromised by some unforeseen circumstances — and by Rendon.
First, Bellinger, while still hitting at an elite level, suffered a midsummer drop-off in performance, losing more than 100 points of on-base-plus-slugging percentage since early July (or 200 points since late May). Then, on Sept. 10, Yelich, who by that point appeared to have seized the lead in the MVP race, had his season come to an end with a broken kneecap.
Now, with little more than a week left in the regular season, the NL MVP race is a fascinating, ever-shifting equation that includes at least Rendon, who has played himself into consideration with a blistering second half, if not Arizona’s Ketel Marte as well. And it’s possible the winner could be decided by how well Bellinger and his closest pursuers perform in the season’s final days.
You can still build a strong statistical case for Yelich and Bellinger.
Yelich entered Friday still leading the NL by a wide margin in OPS (1.100) and many advanced stats — but his odometer is stuck on 130 games, which would be the fewest by an MVP winner (not counting pitchers) since Barry Bonds played 130 in 2003.
Bellinger has numbers just a notch below those of Yelich but has the added attribute of having been, at least statistically, one of the top defensive players in the game while shifting among right field, first base and (more recently) center field.
Rendon entered Friday leading the NL in old-school stats such as batting average (.330) and RBI (119, tied with Atlanta’s Freddie Freeman), and he has put up better numbers across the board in the second half than Yelich and Bellinger — all while playing his typical, elite-level defense at third.
But these days, MVP races are largely about one stat: WAR. Wins above replacement is a catchall stat designed to distill a player’s overall value into one handy number that, by adjusting for factors such as ballpark effects and era, can compare players from different leagues or even decades.
For better or worse, MVP voting has become little more than an accounting of WAR — a stat that, after all, purports to answer empirically the same question (which player has the most value?) that voters are tasked with deciding. The past six MVP awards, three in each league, have gone to the position player who led his league in WAR. (All WAR figures cited here are from Baseball-Reference; FanGraphs calculates its own version of WAR, which differs slightly.)
To that end, here was the NL’s WAR leader board entering Friday:
Here’s where things get interesting, if also a bit convoluted: A sizable chunk of Bellinger’s lead is the result of the way the metrics evaluate his defense. Using offensive WAR alone, Rendon, at 6.4 entering Friday, ranked ahead of Bellinger (6.3) — but still behind Yelich (7.3) and Marte (6.6).
A stat called Defensive Runs Saved above average, which aims to quantify a player’s defensive value based on plays made, ranked Bellinger — at 24 runs saved entering Friday — as the best defensive player in the NL at any position. (Rendon, for what it’s worth, ranked 198th, with two runs saved — which should shock anyone who watches him play stellar defense on a nightly basis.)
How can Rendon, who plays a more difficult position, lose so much defensive “value” when measured against Bellinger, who has spent the bulk of this season at right field and first base — especially when both are considered at least above average and at best elite? Good question.
The metrics behind WAR account for the differing values of each position and adjust accordingly, with a full-time third baseman earning roughly one win more than a player who splits time between right field and first base. But that only makes Bellinger’s lead over Rendon all the more baffling.
The answer could be in the way the metrics rate a player’s defense in comparison with his peers at the same position. A superior right fielder/first baseman — positions where teams typically stash their worst fielders — could grade better than a great third baseman, especially in a season in which there are four NL third basemen (Miami’s Brian Anderson, Atlanta’s Josh Donaldson, St. Louis’s Tommy Edman and Colorado’s Nolan Arenado) who ranked in the top 50 of Defensive Runs Saved above average entering Friday.
Ultimately, those issues will have to be sorted out by the voters, and to that end there are signs the MVP race is tightening. In MLB.com’s most recent monthly poll of its own reporters — not the same group that will vote for the official award, but there is some overlap — Rendon earned his first first-place votes of the season, five of them out of 38 cast.
He still trailed Bellinger (22 first-place votes) and Yelich (11) by sizable margins, but growing support for Rendon would suggest he at least has a tiny chance, with a dazzling finishing kick, to steal the award — and ruin the Belli-vs.-Yeli narrative for good.
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