Corey Kluber Is the Best Pitcher in Baseball

For a really long time, there was little doubt about the best pitcher on the planet. Clayton Kershaw has been on an epic run that will land him in the Hall of Fame. Over the past two seasons, Kershaw has still been brilliant, but he’s averaged 24 starts and 162 innings instead of 32 starts and 222 innings. That slight downturn in health has allowed arguments to pop up debating whether Kershaw is still the best pitcher in baseball. Last season, Max Scherzer was the takeover candidate of choice. The 2016 National League Cy Young winner followed up one great performance with another by claiming the award again. Ignored in those debates was a pitcher who has been better than both over the past two seasons and projects to be better this year: Corey Kluber.

On Monday, Kluber pitched eight scoreless innings, striking out 13 batters against one walk and just two hits. After three starts, Kluber’s ERA is 1.57, his FIP is 2.33, and he’s been worth 0.7 WAR. That’s great, but it doesn’t really separate him from a bunch of good pitchers off to great starts, including Scherzer, Dylan Bundy, and Gerrit Cole. Let’s extend to the past just a little bit more to get a sense of how Kluber has done lately. The table below shows the top pitchers by WAR since the All-Star Break last season.

Kluber is so far out ahead of the pack, the 1.3 WAR difference between him and Severino is nearly double the difference between Severino and 11th-place Scherzer. Combining his great second half with his strong start to this season, Kluber has struck out 169 batters and walked only 15. Since the All-Star Break last season, Kluber has been the best pitcher in baseball, and it isn’t particularly close. To really take a look at the best pitcher in baseball, it probably helps to take a bit of a longer view.

Kluber’s first full season as a starter was in 2014, when he won his first AL Cy Young award. This next table looks at pitcher WAR since that year. It really shouldn’t be a surprise that Kershaw tops the list, but it might be a bit of a shock to see just how close Kluber is to the greatest pitcher of this generation.

There’s really a top four of Kershaw, Kluber, Sale, Scherzer, and then a pretty sizable gap before David Price enters the picture. FanGraphs leaderboards have a feature where we can look at the past calendar year going back three years. Because we might want to get a little more recent than 2014, here are those past three years.

We again see the same top four pitchers with a big gap before we get to the rest of the very good pitchers. This time, Kluber drops to fourth with his 2014 Cy Young season out of the picture, but all four pitchers are separated by barely more than one win above replacement. So what happens when we look at the past two calendar years?

Again, we see the same top four, but this time Kluber takes the top spot. Kerhsaw’s health dinged him up enough to drop him down the list a bit, but still within range of Kluber, Scherzer, and Sale despite 100 fewer innings. It’s pretty amazing how much better these top four pitchers are than the rest of the league. Kluber, Scherzer, and Kershaw have combined to win seven of the last 10 Cy Young awards handed out over the past five seasons.

So what about the past calendar year? Kluber has the top spot by a decent margin.

Kluber is helped slightly by the fact that his first two starts of 2017 weren’t great, so getting rid of those helps push him ahead of Sale. No matter how you look at it, this year-long run for Kluber has been amazing. Since Randy Johnson put up 9.6 WAR in 2004, the only pitchers to pitch a full regular season and put up at least 8.4 WAR are Kershaw in 2015 (8.5 WAR) and Zack Greinke in 2009 (8.6 WAR).

One other consideration in determining the current talent level of a pitcher is projections. Before the season started, Kluber and Kershaw ranked 1 and 2 in ZiPS and Steamer projections, with Kluber taking the top spot in ZiPS and Kershaw first in Steamer. Our Depth Chart projections combine the two and gave the edge to Kluber. Here’s how those pitchers ranked in the various projections systems, along with the other pitchers to place a projection among the top five by either service.

Just a couple weeks into the season, here’s what the rest-of-season projections say.

Corey Kluber projects to be the best pitcher in baseball this season. If we were to scale the projections on a per-inning basis, Kershaw would actually take the lead over Kluber by a couple of runs. Given Kershaw’s innings totals over the past few seasons, it seems fair to dock Kershaw by a few innings, like the Depth Charts projections have done. Even if Kershaw does match Kluber in innings this season, with Kluber’s head start, he would still be projected to finish with a higher WAR than Kershaw. Corey Kluber didn’t pitch a full season in the majors until he was 28 years old. He was a little late to the big leagues, so it is only fair that he’s a little late to this debate. Max Scherzer and Clayton Kershaw made headlines in 2017, but in 2018, it should be Corey Kluber’s title to lose.