From a purely traditional standpoint, Robbie Ray had an incredible 2017. He won 15 games, struck out 12 batters per 9 innings, and had a 2.89 ERA. Including last season, he has a career record of 29-36 with an ERA of 4.07. That’s what makes his 2017 so remarkable. That type of turn around is rarely seen. What happened that allowed this dramatic change to occur?
Robbie Ray got lucky. Really lucky.
The only unsurprising thing about Ray in 2017 were his strikeout numbers. Over the past two seasons, he has struck out 11 and 12 batters per nine innings respectively, which to me means that this is something he can maintain. His ground ball rate of 40.3% was actually below his 42.7% career average, and his 3.72 FIP was below a career mark of 3.77.
Outside of those metrics, Robbie Ray had no business being as successful as his record and ERA can be perceived. For starters, a .267 BABIP is insanely low, especially compared to the .352 mark he saw in 2016, and the league average last year was around .296. He gave up more fly balls than his career average and more hard contact than ever, but somehow still only managed to give up a .197 opponents batting average. On top of all of that, Ray stranded an astonishing 84.5% of base runners. League average is somewhere between 70-72% according to FanGraphs. What is the reason for this?
Ray credits his curveball for a good portion of his success. He threw it 21.9% of the time in 2017, way up from 5.3% in 2016. He threw a slider 18% of the time, the same as 2016, and his fastball usage dropped from 71.1% in 2016 to 59.3% in 2017. Were hitters thrown off balance that much by his curveball? I do really like the pitch. He’s got sharp movement and throws it at 82 MPH. As a left handed pitcher, the curveball is a huge weapon, especially against right handed batters, who Ray held to a .292 average compared to .216 vs. lefties
Unsurprisingly, Ray also put up better road numbers than he did at Chase Field. With the recent announcement that a humidor will be used at Chase Field this season, it is expected that the HR numbers will drop. It has been estimated that home runs could decrease by 25%, which if you use the 93 given up by Dbacks pitchers at home last year, could see them give up somewhere around 70 this year. Taking at least 20 runs off the board over the course of a season can be the difference in adding a few wins, but let’s not forget that this will also impact the homeside hitters as well. The humidor will likely have a positive impact on Ray, as he has always given up his fair share of home runs.
I have a hard time believing that we will see a repeat season from Ray. With his BABIP likely regressing to the norm along with his LOB%, those 4 walks per 9 innings and a high HR/FB will lead to a serious jump in the runs allowed department. If the curveball isn’t solved by batters, maybe he gets close to what he put up in 2017. A 10-10 season with a 4.00 ERA is what I expect to see based on average numbers.