Colorado Rockies: It’s time to stop calling Jon Gray “mentally weak”

Colorado Rockies’ ace starting pitcher Jon Gray struggled through an incredibly tough 2018 season, a campaign that saw him get demoted to Triple-A Albuquerque for a couple of starts with the hope of getting him back on track, as well as being left off of the postseason roster. What was the cause of his struggles last season? What changed between his standout 2017 season and his underwhelming 2018?

There’s something we need to discuss.

Since Jon Gray gave up four runs on seven hits while recording just four outs in the 2017 NL Wild Card Game, a narrative has taken off that he can’t handle the big moments, and that he’s “mentally weak.” Gray’s extremely tough 2018 season didn’t help put this storyline to bed, either.

First, let’s dig into the numbers. When it was all said and done, he finished last year with an ERA of 5.12 in 31 starts. He threw 172.1 innings in those 31 starts, struck out 183 hitters and walked 53, one of which was intentional. The numbers that stand out to me are his 180 hits given up, 102 runs allowed (98 earned, which led the NL) and 27 home runs surrendered. Every one was a career-high.

It’s worth taking a look at his advanced peripheral stats as well. His fielding independent pitching (FIP), which essentially gives you a better idea of what his ERA would have been had he experienced league-average results on balls in play and league average timing, according to Fangraphs, was 4.08, more than a full run lower than his ERA.

His ERA+, which is a park-adjusted version of ERA that tells you how much better or worse the league was than a certain pitcher, was 92. This means that the league ERA was eight percent lower than Gray’s. Below average, yes, but not absolutely terrible.

Let’s compare this to his 2017 season, when he earned that Wild Card start. He finished that year with a 3.67 ERA in 20 starts (he suffered a stress fracture in his left foot in an April start in San Francisco that put him on the shelf for an extended period of time).

He gave up 47 total runs (45 earned) on 113 hits, he struck out 112 hitters and walked 30. His FIP was 3.18, much closer to his 3.67 ERA, and he posted an ERA+ of 138. We can all agree that his 2017 was much better.

A quick look comparing some of Gray’s other 2017 peripheral stats with those from 2018 reveals some surprising similarities. His K% was a tick better in 2018 than it was in 2017 (24.6 vs 24.3), as was his K/9 (9.56 vs 9.14). His BB% was just 0.5 percent higher in 2018 (7.0 percent) than in 2017 (6.5). His batting average against was identical between the two seasons (.263). His WHIP? 1.35 in 2018 vs 1.30 in 2017. His BABIP (batting average on balls in play) was actually lower last season than it was in 2017 (.322 vs .336).

A search on Baseball Savant reveals something even more bewildering. Gray’s swing & miss % on each of his four main pitches increased from 2017 to 2018, except for one: his changeup.

Changeup: 43.8 percent to 33.3 percent

Fastball: 12.6 to 17.5

Slider: 34.3 to 38.2

Curveball: 36.0 to 41.8

Where we can start to see the problem lies in his average exit velocity of all of his pitches. It increased from where they were two seasons ago on all five pitches he utilized:

Fastball: 88.3 mph to 90.5 mph

Curveball: 85.4 to 86.3

Changeup: 83.3 to 89.6

Sinker: 79.8 to 88.1

Slider: 77.8 to 87.3

When Gray was hit, he was hit hard, a lot harder than in 2017. Most notably his slider, a pitch he used 34 percent of the time, left the bat almost 10 mph faster, on average.

Staunch Jon Gray supporters who cited these peripherals were often criticized for “making excuses” for the maligned starter. There is some merit to that, because at the end of the day Jon Gray simply did not live up expectations and help the Rockies win games. But getting back to the headline, I believe it is irresponsible, and unfair to Gray, to claim that he is suddenly “mentally weak” without any kind of input from a psychologist. I do not believe stating that Gray had an incredibly unlucky season, as these peripheral stats suggest, and that he simply wasn’t good enough are mutually exclusive.