The Diamondbacks have landed the best free agent starting pitcher available this year, signing Corbin Burnes to a six-year deal worth $210 million that offers the pitcher a chance to opt out after two years. That’s a lot of money — Burnes now has a top-ten average annual value among all players, and is behind only Zack Wheeler, Jacob deGrom and Gerrit Cole among pitchers. His pact represents the fourth-largest overall contract handed to a pitcher in the history of baseball.
It’s a great deal for both the player and the team. Burnes is getting paid, and the Diamondbacks get a stud.
Over the last four years, Burnes is second in FanGraphs WAR to Wheeler, with an identical ERA (2.94). Only three pitchers have thrown 600+ innings in that time frame and kept their ERA under three — Burnes, Wheeler and Max Fried. He combines the ability to strike guys out (third among starters in the last four years) with the demonstrated skill of getting ground balls (eighth) and limiting walks (14th), and he’s kept the velocity on a 95 mph cutter that’s one of the best single pitches in baseball. If he maintains that excellence, he can jump back into the market at 32 and get another deal like this or better.
In other words, he’s absolutely a stud in the regular and post-season, and an ace’s ace.
The risk, then, for Arizona is two-fold, as it’ll be on the hook for four more years if Burnes decides not to opt out. First, is the declining strikeout rate indicative of stuff that’s aging poorly. And second, what happens if the injury bug comes calling?
It’s true that there has been a slight decline in the physical characteristics of Burnes’ pitches, and that his strikeout rate has fallen from 35.6 percent in his first full season as a starter to 23.1 percent last year. His cutter has seen better days, as it lost around an inch of drop this year and twenty-plus points of Stuff+ over the last few years. He’s gone from a 17 percent whiff rate in 2021 to a 10 percent whiff rate this past season on the pitch. Aging comes for everyone, and it’s possible that his cutter won’t return to the dominance it once had.
But there’s actually some good news here. For one, even a lesser version of Burnes was still top five among starting pitchers in Stuff+, so he’s still been great after a reduction in nastiness. Late last season, though, something changed in the cutter for Burnes, as he found his old drop again in late August.
From that moment on, the Stuff+ was back to best in baseball among cutters. He produced a 13 percent whiff rate on the pitch, and his overall strikeout rate was back to 26 percent. That’s not quite back to the thirty-plus rates of his first couple years on the scene, but it’s a good sign that he’s at least got his bread and butter back.
In the meantime, there are a couple other good signs that he’s accumulated along the way.
He’s become a bit more of a pitcher than a thrower. For one, he’s increased the usage of his breaking balls in a more diverse arsenal. And then there’s his ability to manage contact. Over the last two seasons, even while his strikeout rate has come down, he’s been able to keep hitters off the barrel. He’s tied with Tarik Skubal for the sixth-best Barrel rate allowed and the third-best Hard Hit rate. With all the spin and command Burnes shows, he’s been able to reduce damage if the ball is put in play.
Secondly, he’s experimented with a pitch that could make him even better. With such a great cutter, it might not be a surprise that Burnes has reverse platoon splits and has been better against lefties than righties for his career. Across baseball, the pitch that has performed the best righty-on-righty is the sweeper. Late in both 2023 and 2024, Burnes started flashing a plus version of this pitch.
With Burnes’ obvious feel for spin, this seems like a good sign. At the very least, it shows that Burnes has the ability to add to his arsenal, and that he won’t be stuck doing the same thing as he ages. This sort of adaptability bodes well.
The great equalizer on all pitcher deals is injury, of course. But a couple factors there also suggest that Arizona is well-positioned to do well here. For one, it’s ‘only’ a six-year deal. Put up against Yoshinobu Yamamoto’s 12-year deal, Cole’s nine-year deal, and Fried’s eight, and it’s obvious the Diamondbacks won’t be burdened as long as some other teams if things go poorly.
Will things go poorly? Predicting injury is a very difficult thing. Though the rate of Tommy John surgeries has steadied over the last three seasons, the number of injury days lost by pitchers has only seen increases. Jeff Zimmerman has done research trying to predict health, and has found factors like age, fastball velocity, career injured list days, recent injured list days, and arm injuries can be combined to produce a health grade. Burnes does well in his estimation, with a top-ten health grade going into 2024.
The median innings pitched for starters with an “A” health grade like Burnes’ is 174, so he seems as good as any pitcher to bet on for innings in the next few years. Combine that with his recovered cutter, nascent sweeper, and demonstrated excellence, and it seems like the most likely outcome is that the Diamondbacks just got one of the best five pitchers in baseball on a short-term deal. Even with the reports that he turned down more from other teams, it’s a little surprising no mystery team blew this offer away.
Arizona did well.
(Photo: Patrick Smith / Getty Images)
