Over the past few days, the hot stove has gotten rather toasty with rumors of the Detroit Tigers checking in on a host of free agent pitchers. Obviously Justin Verlander was the most prominent of that group, but perhaps not the most likely. Former Colorado Rockies starter Jon Gray doesn’t have that kind of upside, but he’s less risky. The Tigers’ pitching coaches did a nice job with their staff in year one, and removed from the unfriendly confines of Coors Field, perhaps Gray could find another gear in Detroit. The Tigers appear to be interested, and so are we, so let’s take a little deeper look into his numbers and future potential.
Gray is a former first-rounder, taken third overall by the Rockies back in the 2013 amateur draft. Now 30 years old, the right-hander has been a source of stability for a typically beleaguered Rockies rotation over the past seven years, but has never broken out the way many expected. On the plus side, he has been pretty durable and overall his numbers are fairly strong considering his home ballpark.
Jon Gray 2018-2021
Physically, Gray is your prototypical power right-hander, standing six-foot, four inches and weighing in officially at 225 pounds. At times he’s had some minor injury issues, but overall they’ve rarely kept him off the mound for more than a start or two. While he’s never approached the 200 inning threshold, he’s a very good bet to give you 150 innings or more. He hasn’t missed many starts over the past three full seasons, averaging 28 starts across 2018, 2019, and 2021, but also doesn’t tend to go as deep into games as you’d like.
While he’s tried to mix in more changeups in recent seasons, Gray is basically a two-pitch pitcher, featuring his fourseam fastball and slider almost exclusively. The curveball and changeup are typically just for a change of pace to left-handed hitters. He certainly collects his share of strikeouts, and isn’t all that home run prone considering the Coors Field effect. But he does tend to struggle in the middle innings. Adding a little depth to his arsenal in the form of a more effective third pitch would be a key point of emphasis to any team signing him this offseason. The hope, is that with an extra wrinkle added, and a more favorable park to pitch in, Gray might last an inning or two longer than his heavy fastball-slider approach has generally allowed.
The fastball averaged 94.9 miles per hour in 2021, which is almost a full tick higher than in 2020. It’s a low spin model that sinks rather than riding through the zone, and gets almost five inches more horizontal break than average. He doesn’t get a lot of whiffs on the fastball, and it tends to be hit harder than you’d like to see, but the saving grace is that the heater is hard to lift, inducing a lot of ground balls and line drives rather than getting crushed into the seats.
The money-maker is Gray’s slider, which averages 86.7 mph and has nearly straight rifle spin action. He used the slider 38.1 percent of the time in 2021, versus 47.6 percent fastballs, so the slide piece is a huge part of his repertoire and his best pitch. When he’s really going good he adds and subtracts velocity and alters the shape of the slider pretty well too. It’s a versatile weapon for him. He racked up a fine 38.8 percent whiff rate on it this season, while hitters slugged a paltry .300 against.
Beyond the primary offerings, Gray has a 76 mph curveball with below average depth, but some additional horizontal break. Gray only threw it a bit over six percent of the time in 2021, and more against lefties than right-handers, but the pitch drew a pretty good whiff rate at 30 percent. The curve has looked better in past seasons than it did this year, so there is some potential to tune it up a bit.
The changeup is used almost exclusively against lefties, and gets below average depth and fade. Gray’s arm speed and his fastball velocity do help to sell it reasonably well. As currently constructed, the curveball or the changeup aren’t particularly good third offerings, but if Gray and Fetter could improve one of them just a bit, Gray could potentially level up quite a bit pitching in a place like Comerica Park.
We suggested something similar with Anthony DeSclafani last offseason, and he went on to have a really good year getting out of Great American Ballpark and heading to San Francisco. Like Gray, DeSclafani was basically a fastball-slider guy who couldn’t go deep in games and had some home run trouble at times in a tough park to pitch in. He didn’t really change his approach much in San Francisco either, throwing the slider a little more, but still less than Gray already does. Gray is far more established already, but that only lends more credence to the idea that he might look markedly better if he wasn’t making half his starts in Coors Field.
The Coors Field problem
There has been plenty of research done to cut through the fog of the Coors Field altitude effect for hitters, but with pitchers it’s more complicated. Whatever a hitter’s numbers are in a given park, we can still look to exit velocity, launch angle, and barrels to understand their quality of contact off the bat without the effect of altitude being involved. Obviously the ball carries better in the thin air, but the exit velocity off the bat isn’t affected much. However, the effect of altitude on the movement of a pitcher’s pitches is trickier to really unpack. The Rockies have struggled for years to find ways to deal with it, and with scant success overall.
With a slider, for example, particularly a near perfect gyrospin model like Gray’s there is probably very little effect on the movement, as the pitch basically moves with gravity. However, on fastballs and changeups, pitches tend to get less horizontal movement at Coors. The fact that Grays’ fourseamer looks very sinker-ish, and already gets well above average horizontal movement, bodes well for it in other parks, where he should get even better run on the pitch.
In particular, that could help him stay off the barrels of left-handed hitters, who typically get to Gray for more home run power. He likes to attack them with swing back fastballs inside and then running away, going upstairs for whiffs and weak contact when he’s ahead. A little more movement could really help him there.
It’s unlikely that simply moving out of Coors is going to have a huge effect on Gray’s numbers. Players understand the issues present, and tend to adapt and still pitch better at home than on the road. In Gray’s case he has perfectly well-balanced home and road FIP splits in his career. Presumably the move to a big park much closer to sea level, say, Comerica Park for example, would help him, but he’s also had the advantage of pitching to pitchers instead of designated hitters his entire career. The combined effect may not produce much change in his numbers.
The Tigers seem interested
We’re not exactly sure what the Rockies were doing here, and we’re not alone in this. They decided not to trade Gray at the trade deadline, despite plenty of interest. He’d posted an excellent first half, with his numbers really collapsing in September, so his trade value was in great shape. However, the Rockies apparently thought they could convince him to sign an extension.
A rumored offer of three years, $35-40M recently wasn’t enough to get the job done. But then the Rockies doubled down by declining to make a qualifying offer to Gray. Now, they stand to lose him and get nothing in return. This is the kind of thing that makes a baseball writer want as much former Rockies’ talent as possible. There seems to be some sustained dysfunction over there to put it mildly.
The fact that interested teams won’t have to give up a compensation pick to sign Gray only makes him more attractive. However, as a pitcher who is typically in the 2-3 WAR range, we’re also not looking at a star who is going to command a huge, long-term deal here. Teams also have to consider the fact that Gray missed a start in early September with forearm tightness, and while he came back for five more outings, he still looked rather out of sorts. On the other hand, his velocity was just fine, but the final month prior to free agency isn’t a great time for issues to crop up.
FanGraphs projected a three-year deal worth $39M, averaging $13M per season, but of course Gray has apparently already turned down similar money from the Rockies. That may simply be a desire to escape the situation in Colorado, but it doesn’t mean the Tigers would be high on his list of teams to join.
Gray certainly seems likely to benefit from a new home, and as long as he’s basically healthy, would make a good addition to the Tigers rotation in 2022. However, there is enough interest, and the attraction of getting him out of Coors too well known, that he may not be much of a bargain either. If the Tigers could land him for three years and $42M, we’d be pretty comfortable with that, but wouldn’t want them chasing him much higher unless the Tigers are both quite confident in his medicals and really think they can unlock significant improvement.