Sunny Days Have Returned for Sonny Gray

Early in the season, Luis Castillo was the pitcher drawing eyeballs in the Cincinnati Reds rotation. After showing flashes of elite potential in his first two seasons in the big leagues, the right-hander had reached new heights with his ridiculous change-up, and the numbers he posted over the first six weeks of the season had him getting serious attention as a Cy Young favorite. After years of abysmal pitching staffs, the Reds finally looked like they had an ace on their hands.

A couple of months later, however, Castillo’s been surpassed in WAR by a teammate who once garnered ace buzz at a similar age. In 21 starts, Sonny Gray has been worth 2.7 WAR, thanks to a solid 3.51 FIP to go with a 3.47 xFIP. Castillo has had trouble with walks as the season has progressed, but overall, his numbers remain fairly strong, and optimism surrounding him is deservedly high. Quietly, though, Gray has been every bit as good.

While Castillo entered the 2019 season with the expectation that his best years were ahead of him, Gray faced the question of what he had left to offer. He picked up 7.4 WAR from 2014-15 with the Oakland A’s, finishing third in Cy Young voting in the second of those seasons. His ERA ballooned to 5.69 in 2016, but he returned to approach another 3 WAR season between Oakland and New York the following year. That paved the way for a truly head-scratching 2018 season in which his home-road splits reached absurd levels, and he failed to stick in the rotation, allowing a 5.26 ERA in 23 starts. Viewing him as a lost cause, the Yankees were determined to trade him last offseason, and found a match with Cincinnati in January.

At the time, the Reds seemed like a curious landing spot for Gray. The organization has a poor track record of developing or repairing pitchers, and its home park was hardly more pitcher-friendly than Yankee Stadium, where Gray seemed to fall somewhere close to yips territory as the season dragged on. But Gray would also be reuniting with his college pitching coach Derek Johnson, as well as two other fellow Vanderbilt alums in catcher Curt Casali and pitching assistant Caleb Cotham. And for as sorry as his 4.90 ERA appeared, his 4.17 FIP and 4.10 xFIP suggested there might be something there worth working toward. The Reds signed Gray to a three-year, $30 million extension through 2022 with a $12 million club option for 2023, and the two sides went to work attempting to restore the 29-year-old to his former self.

Now, we’re a day from the trade deadline, and Gray once again looks positively inspiring. His strikeout rate is by far a career best, up to 10.2/9 from an 8.49/9 mark in 2018, his walk rate has dropped from 3.94/9 to 3.06/9, and his groundball rate is up by 4%. Put it all together, and Gray’s FIP- of 78 is his best since his rookie season, in which he threw just 62 innings.

Gray’s found this dominance again by leaning into his strengths. He has always boasted high spin rates, and in 2019, he has generated more spin on his breaking ball than ever before. That has helped him generate some of the best slider and curve movement in the majors. According to Statcast, he gets the third-best horizontal movement and 15th-best vertical movement in the majors with his slider, while the horizontal movement on his curveball ranks 11th.

The filthiness of those two pitches is pretty clear. Here’s Gray sitting down Christian Yelich with a slider:

And here’s a curveball from that same game — note that it is Gray’s 105th pitch of the game:

Those two plate appearances are good examples of the results Gray has been getting with his breaking pitches. His slider has resulted in a .148 wOBA from opponents, while his curve has generated a .203 wOBA. That’s the best value of his career with the slider, and the best with his curve since 2013.

While his breaking pitches have each taken steps forward, though, much of the rest of Gray’s profile doesn’t appear to be meaningfully different. His velocity has been consistent over the last two seasons, and so has plate discipline numbers such as chase rate and contact rate. Despite these parts remaining the same, the sum has been quite different.

It’s difficult to say what makes a pitcher qualify as an ace. On the surface, it seems like an ace is a pitcher in the top 30 in baseball. There are 30 teams, after all. Others, however, might say the game’s true aces form a much more exclusive club, reserved for only five or six pitchers at a time, separating the elite from the rest of the pack. I think I fall somewhere in the middle. In my opinion, if you’re one of the top 15 pitchers in baseball, you’re an ace. That number trims a lot of fat, but also doesn’t make the club so small that only a handful of teams can claim to have one at any given time. Entering Monday’s start, here’s where Gray ranked among all qualified starters in a wide range of pitching categories:

The walk rate isn’t impressive, but the rest of those numbers show some notable consistency. While he doesn’t stand out in anything except groundball rate, Gray sits somewhere in the 10-20 best pitchers in the game across the board. That’s quite impressive for someone who was shopped so openly just a few months ago because of concerns he couldn’t stick in a rotation, but it’s also impressive when thinking about how Gray compared to the rest of the league when he was at his previous peak. In 2015, Gray was third place in Cy Young voting, leaving little to no doubt that he was among the game’s aces. Here’s the previous table again, with the addition of how he stacked up to the rest of the league in the same categories in 2015:

His ERA was outstanding, and he was still a great groundball pitcher. But overall, the 2019 version seems to be the better one. If 2015 Gray was worthy of prominent Cy Young consideration and was seen as an ace, what does that mean for 2019 Gray?

Well, there is one more difference between the 2015 season and 2019. In 2015, Gray threw 208 innings, the 17th-highest total in baseball. This year, he’s thrown 114.2 innings — 54th-highest total in baseball. Extrapolated over 32-start season, Gray is on pace for just around 170 innings, a number that 50 pitchers surpassed a year ago. That brings up an interesting question: Should innings totals factor into the discussion of whether someone is an ace? As baseball has evolved in recent seasons, more and more innings are being handed to relievers, as the 200-inning starting pitcher becomes more of a rarity. In that 2015 season, for example, 28 pitchers finished with 200 innings. In 2018, that number fell to 13. Among those 13 were some of the unquestioned aces of today: Max Scherzer, Jacob deGrom, Justin Verlander. AL Cy Young Award winner Blake Snell, however, threw just 180 innings last year. Expectations for aces aren’t what they used to be, and if Gray is this good when he’s in the game, maybe that’s more important than his ability to pitch one out into the seventh rather than one out into the sixth.

Regardless of whether you consider Gray an ace, there’s a good chance he’s closer to that territory than you’d initially suspect, and he’s undoubtedly closer than he’s been in years. It’s been even longer since the Reds had an ace themselves. After a long span of historically bad starting rotations, Cincinnati has experienced something of a renaissance with this year’s staff. To this point, no one has factored into that more than Gray.