“Clayton Kershaw is the best pitcher in baseball” is a statement that started out around 2011 as a trial balloon, the kind of assertion you feel in your gut but have to prove. As the years wore on and the Cy Young votes racked up, it became an accepted statement of fact, then remained so for long enough that it changed into an article of faith — not only do we know scientifically that Kershaw is the best pitcher in baseball, but we believe it spiritually.
Eventually, we stopped considering the question of “Who is the best pitcher in baseball?” like a golf tournament, where all entrants get equal consideration, and more like the America’s Cup or the World Chess Championship — a select group of elite challengers are pitted against one another for a chance to face the final boss.
The most recent challenger is Nationals right-hander Max Scherzer, who’s currently leading the National League in strikeouts and all of baseball in ERA+. Meanwhile Kershaw is seemingly in decline, on pace to more than double his career high in home runs allowed and post his lowest K% since 2013, with his highest FIP since his rookie year. Kershaw’s been challenged before, but mostly by newcomers like Jake Arrieta, Noah Syndergaard, Matt Harvey, and the late José Fernández, men whose arguments rested on “stuff” or “potential” and were usually couched in terms of the future anyway.
Scherzer’s is the most serious challenge yet, not only because Kershaw looks vulnerable, but because Scherzer is not only good now, he’s been good for long enough to generate a track record that makes it impossible to dismiss him as a fluke. Scherzer came into this season riding a streak of four straight All-Star selections, four straight 200-inning seasons, and eight straight 30-start seasons, all of which would be impressive enough, but he’s also posted an ERA+ of 140 or better in three of the past four seasons and struck out 230 or more batters every year since 2012.
Scherzer also has a unique ability to put together monstrous single-game performances. In 2015, he had a 16-strikeout, one-hit, one-walk complete-game shutout and a 10-strikeout no-hitter in back-to-back starts, then finished the season with a 17-strikeout no-hitter in which the only base runner reached on an error. In May 2016, he became just the fourth pitcher (after Roger Clemens, Kerry Wood, and Randy Johnson) to strike out 20 batters in a nine-inning game, and in the past month, he flirted with another run at the strikeout record and a third no-hitter.
But that durability and penchant for single-game brilliance wouldn’t matter if Scherzer hadn’t been out-pitching Kershaw this year, and he is, conclusively, outpitching Kershaw this year.

It’s a challenge serious enough to merit at least lukewarm backing by legendary sabermetrician Bill James and MLB Network host Brian Kenny, Neil Greenberg of The Washington Post, FiveThirtyEight’s Elo rating system, and veteran columnist Danny Knobler. Not exactly an overwhelming popular consensus, but enough of a groundswell to make the question worth asking: Is Kershaw still the best pitcher in baseball?
Scherzer’s the most credible challenger to Kershaw since he took the title off of (depending on who you ask) Roy Halladay in 2011 or Justin Verlander in 2012 or 2013, but Kershaw’s still the champ, and it’s still not all that close.

Nobody who says “Best pitcher in baseball right now” actually means it, because baseball is, more than any other major American sport, a game that requires sustained excellence over time. Unless it’s Game 7 of the World Series, it’s not good enough to be good now, you have to be good six days a week over a six-month regular season. Multiple six-month regular seasons, really, if a player has ambitions of being anything more than a one-year historical curiosity, like Mark Fidrych or pre-yips Rick Ankiel.
Last week, Yu Darvish struck out 10 with no runs, no walks, and two hits on 88 pitches over seven innings, but even though he was the best pitcher in baseball on Friday, and he’s got some of the best stuff in the game, nobody’s calling him the best pitcher in baseball over any time horizon. Darvish walks too many batters, and he’s broken the 200-inning barrier only once — he’s great at times, but not consistently great enough to be considered a threat to Kershaw the way Scherzer is.
So, track record matters. The question is how much.

Scherzer debuted a month before Kershaw in 2008. That year, Scherzer posted a 151 ERA+ and a 10.6 K/9 in 56 innings split between the rotation and the bullpen in Arizona. Kershaw, who threw the most famous called strike in spring training history that March, made 21 starts and one relief appearance and struggled to throw strikes at times (4.3 BB/9), but posted a 98 ERA+ in 107.2 innings, which is great for a 20-year-old but not good enough to make the Dodgers’ playoff rotation that year.
Kershaw allowed the fewest hits per inning in the majors the next year, and by his age-23 season in 2011, he’d halved his walk rate from his rookie year and led the league in strikeouts en route to his first Cy Young Award.
Scherzer, despite being four years older, took a little longer to develop. A University of Missouri product, Scherzer was, for a time, the first of what’s now a decade’s worth of pitchers who turned Mizzou into the University of Right-Handed Pitchers With Big Stuff They Can’t Quite Harness. (Others include former Royals reliever Aaron Crow, 2017 Red Sox first-rounder Tanner Houck, and 6-foot-7, 261-pound Bryce Montes de Oca.) Scherzer’s been at least pretty good since the moment he hit a big league mound, but it wasn’t until his late 20s that he learned to throw strikes and miss bats at the same time, a development that earned him a K/9 title in 2012, when his K/9 ratio jumped from 8.0 all the way to 11.1, and his first Cy Young in 2013, when he set new full-season career lows in BB/9 and H/9, reducing the latter by 20 percent.
We don’t need a decade’s worth of data to evaluate the best pitcher in baseball today — when Kershaw won his first Cy Young, his competitors for the Best Pitcher in Baseball title were Halladay and Cliff Lee, both now retired, and Félix Hernández and Verlander, now both on the decline. But over their overlapping careers, this is the longest Scherzer’s been better than Kershaw.
Not counting 2017 or Kershaw’s 2016, when he didn’t qualify for the ERA title, here’s how many times Kershaw’s been better than Scherzer’s career best over a full season:

(DRA- is a league-adjusted ERA estimator from Baseball Prospectus.)
Even the FiveThirtyEight Elo rater, which is in its third week in a row with Scherzer in the top spot, had Kershaw there for 37 of the previous 38 weeks, and 106 of the previous 139.
But Elo is a rolling weighted measure, so if Scherzer’s on top now, it doesn’t just mean that he’s better right this instant, he’s been better over a long period of time. The reason for that is a point that Brian Kenny hit hard: Since 2014, Kershaw’s pitched almost 100 fewer innings than Scherzer, which is important in an era when it’s no longer a given that a pitcher will stay healthy throughout his prime. That’s allowed Scherzer, despite being nowhere near as good on a rate basis, to move into a virtual tie with Kershaw in bWAR (23.3 for Scherzer, 23.6 for Kershaw) over the past three and a half seasons and overtake him by about a little more than a win (17.3 to 16.1) over the past two and half.
That’s not nothing, but it’s also not exactly what it looks like on the surface. First, 1.2 WAR isn’t that big a difference, and Scherzer’s whole lead is based on his performance this season. Second, unlike runs and strikeouts, which can be measured, WAR is a statistical model. A professor of mine used to say, “All models are wrong, but some models are useful.” Certainly WAR is useful, but it’s not a divine instrument — it only values what the people who designed it tell it to value. To reuse an old metaphor of my own, WAR is a roller and sometimes you need a brush — especially when you’re comparing just two players.
What that WAR total doesn’t tell you is that while Scherzer’s nearly 100-inning edge is huge, Kershaw isn’t exactly Rich Hill — he made 33 starts in 2015 and leads the NL in innings pitched in 2017, to say nothing of the four straight 200-inning seasons he banked from 2010 to 2013. And even though he missed six starts with a shoulder injury in 2014, Kershaw still threw 198.1 innings and won not only the Cy Young but the MVP Award as well.
Even last year, when the BBWAA gave Scherzer the Cy Young over Kershaw (a decision I agreed with), who missed a third of the season with a back injury , there was still an argument to be made that Kershaw was the best pitcher in baseball anyway.
Last year, Kershaw missed qualifying for the ERA title by 13 innings, or about two starts. If he’d made it that far, his 235 ERA+ would’ve been the 10th-best in history, and the best since Pedro Martínez in 2000. His 15.64 K/BB ratio would have demolished the current record of 11.63, set by Phil Hughes in 2014. Despite throwing almost 80 fewer innings than Scherzer, Kershaw came within 0.6 of a win of matching his National League–leading WAR total. And it’s not like Scherzer blew away the field in 2016 with Kershaw hurt — six National League pitchers, including Kershaw, finished within a win of Scherzer, and that doesn’t count Kyle Hendricks, who led the league with a 190 ERA+ in 190 innings and finished third in Cy Young voting.
Scherzer’s been in the middle of a Hall of Fame peak since 2012, while Kershaw’s in the middle of an all-time great peak since at least 2011, and the difference between the two is large enough that Scherzer didn’t really put a dent in it at any point last year.

In 2017, Scherzer’s absolutely been the better pitcher, and Kershaw’s absolutely been worse this year than at any point since he won his first Cy Young. But “worse” for Kershaw is better than almost any other pitcher in the game.
Even while in a tailspin that feels like a crisis, Kershaw’s season ERA+ is 171, a mark that Scherzer’s yet to match over a full season. And for as unforgivable as it is to allow four home runs in a game to the Mets, Kershaw’s inability to keep the ball in the yard isn’t as big of a problem as it looks. Home runs aren’t somehow more special than other kinds of runs, particularly during the Fly Ball Revolution (which would be a great name for a baseball-themed novelty band, in case anyone wants to take that one for free).

Even if you were to make an argument that Kershaw’s newfound homer-prone-ness somehow disqualifies him from being the best pitcher in baseball, Scherzer’s not the guy to elevate: Scherzer’s allowed 12 home runs this year without anyone batting an eye, and last year he won the Cy Young despite tying for the NL lead in home runs allowed (31).
This year, Scherzer and Kershaw have thrown about the same number of innings (107.2 for Scherzer, 109.1 for Kershaw), and allowed almost the exact same number of runs (31 for Scherzer, 32 for Kershaw). Kershaw’s allowed 20 more hits, but Scherzer’s allowed 14 more batters to reach by walk or hit-by-pitch. Almost the entire difference between the two has been in Scherzer striking out more batters and allowing fewer extra-base hits — a 0.4 HR/9 edge and a 2.0 K/9 edge, both of which are significant over the course of a season, but not so significant that Kershaw can’t claw back to parity over the second half of the season.
For proof, look no further than the reason we’re having this argument. Remember that 1.2-WAR edge Scherzer has over Kershaw since 2015, and how 1.1 wins of that advantage has come since the start of this season? It’s not exactly true that Scherzer’s been better than Kershaw all year. Here’s how they stacked up after Scherzer’s 8.2 IP, 13-strikeout victory over the Padres on May 26, when both pitchers had started 10 games.

In other words, 31 days ago, the morning after what was at the time Scherzer’s best start of the season, Kershaw was having a better year than Scherzer. Not lap-the-field better, but noticeably better. Everything about the Scherzer-over-Kershaw argument is based on events from the past five weeks, in which Kershaw allowed home runs in five straight starts, while Scherzer’s ripped off a game score of 80 or better four times in six starts.
Five weeks might seem like a lifetime in Trump’s America, but it’s not. Scherzer’s been better over the past five weeks, and he’s kept pace with Kershaw over the most injury-prone portion of Kershaw’s career, but even then, that’s only when they’re judged under criteria (counting stats instead of rate stats) that are favorable to Scherzer.
The pattern that led to this talk of Scherzer being the better pitcher started on May 26 of this year at the earliest. (Kershaw’s ERA didn’t rise above Scherzer’s until June 19, so it might not even have been that long ago.) Meanwhile the pattern of Kershaw being better than Scherzer stretches back to 2009.
Even if Scherzer does outpitch Kershaw over the rest of the season, that won’t necessarily mean he’s eaten away at the lead Kershaw already had. Kershaw’s been out-pitched before, notably by Arrieta in the second half of 2015, but over the past five years, nobody else has been able to keep up with Kershaw for more than a few months, much less surpass him.
Kershaw’s been so far ahead of the competition over the past five years that short of him retiring, it’s almost impossible for that to change in five weeks.

Everyone knows it, too.
The language in these Scherzer-over-Kershaw takes carries little empirical weight, but it’s telling. Knobler said Scherzer “might be” the best pitcher in the game. The headline of Greenberg’s story — “The Nationals’ Max Scherzer is overtaking Clayton Kershaw as MLB’s best pitcher” — is at odds with how, in the second paragraph, Greenberg called Scherzer “the most likely to unseat Clayton Kershaw as the best pitcher in the baseball,” which is true, but much less controversial. FiveThirtyEight’s headline was “Clayton Kershaw Might (Might!) Not Be the Best Pitcher in Baseball Anymore.” Even Kenny, ordinarily the least equivocal voice in mainstream baseball analysis, peppered his four-minute segment on MLB Network with caveats.
That’s not the kind of language people use to contradict an article of faith if they really mean it. True apostasy knows no equivocation. If Scherzer had actually passed Kershaw as the best pitcher in baseball, the takes wouldn’t read like they’re trying to get a study that proved nothing published in a peer-reviewed journal; they’d be definitive.
Max Scherzer is the second-best pitcher of his generation, but Clayton Kershaw is still no. 1. That might change someday, but if and when it does, we’ll know it beyond a shadow of a doubt.