Jake McGee Knows His Spin Rates

If the data age were to help one group of pitchers more than any other, if video and scouting reports and pitch data were to help one club’s pitchers relative to all the other ones, you could make a case it should be the Colorado Rockies.

As we know, the Rockies play in baseball’s most extreme run environment. But it’s not just the predominately negative effects of mile-high altitude that make things difficult for Colorado’s pitchers. It’s that those same pitchers also have to visit 14 other National League ballparks that play much differently than their own park — this after more than a month of training in a different environment during spring, as well. Perhaps it is information that can better guide Rockies’ pitcher in making adjustments from location to location.

Jake McGee struggled at times during his first year in Denver last season, a year when he was also dealing with a knee injury. This year he’s healthy, and this season he’s diving into data more than ever before. The combination has allowed the Rockies to enjoy one of the game’s most dominant relievers through the first third of the season.

The Rockies’ surprising start — surprising to some — has been, in part, fueled by a bullpen that ranks second in the NL in WAR (2.6), and third in ERA- (81). Both McGee and offseason reclamation project Greg Holland are significant reasons for that success.

McGree ranks 16th in among major leaguers in FIP- (51) and 23rd in K-BB% (25.2 points). After Andrew Miller, he has been about as dominant as any left-handed reliever in the game and it is pivot in performance after posting a 4.73 ERA, 5.29 FIP in 45.2 innings of struggle last season.

Yes, he’s healthy, but McGee also says that web sites like FanGraphs and Baseball Savant, along with data he’s requested from the Rockies analytics staff, have allowed him to better use his tools. And it’s basically one tool McGee has: a 95 mph four-seam fastball.

No pitcher in baseball more often throws a four-seam fastball than McGee, who throws it on roughly 95% of his offerings, up from his career rate of 90%.

The pitch has rare velocity from the left-handed side and it also has more rise than the average four-seamer, according to average pitch movement documented by Eno Sarris. PITCHf/x has McGee generating 9.65 inches of vertical movement compared to an MLB average of about eight inches of vertical “rise.”

But the problem was McGee’s fastball, like all fastballs, played much differently at Coors compared to various road venues. McGee struggled with health, and a new environment, in his first year on the high plains of Denver.

McGee said he had begun to “educate” himself on the data tools available when he was in Tampa Bay. When I approached and introduced myself as a FanGraphs writer earlier this week, his locker room neighbor Chad Qualls exclaimed “RPMs!” and McGee echoed it.

“It’s helped me use the weapons. One of the guys who was really big on [data] in Tampa was Burke Badenhop,” McGee said. “He follows it every day and all the sheets and the rise, the RPMs on your fastball compared to your slider.”

McGee found himself more interested in the data during his struggles last year, when he felt his stuff played differently at home compared to the road. McGee is another example of the importance of a player being curious, and reaching out to find an answer. McGee was interested, specifically, in the difference in rise between pitching at home compared to pitching on the road. So he asked for help from the Rockies front office.

“I asked them [the front office] if they could find the difference between at home and on the road, and it was a little under two inches at home compared to the road,” said McGee of vertical movement on his fastball. “On the road, I get higher misses on fastballs. At home, I have to start it higher because it doesn’t rise as much. Little things I’ve learned, adjusted, and had some success with it.”

He has learned his fastball spin rate averages 2243 rpms at home this season and 2228 rpms on the road. Consider that McGee produced 10.26 inches of rise compared to a spin-less fastball when pitching in Tampa and mostly in the AL East in 2015. This season he’s averaging 9.65 inches. They’re subtle differences, but slight adjustments can result in big performance jumps.

Compare McGee’s fastball location this season …

… to last season:

McGee is more often pitching up. Consider some examples of McGee elevating to get a swing and miss earlier this year against the Padres in Denver.

McGee elevating against Jabari Blash:

And McGee elevating to Austin Hedges, a player who is susceptible to the high fastball:

McGee doesn’t get a ton of misses on his fastball despite its velocity and above-average rise, but batters also know what pitch they’re likely to face. But what has been different about McGee this year is he’s getting ahead in counts more often, pitching in the zone more often, and generating weak contact more often.

His fastball has generated the 19th-highest rate of foul balls in the game according to Baseball Prospectus.

Against his fastball, he has the fifth lowest expected weighted on-base average (.203) among all pitchers who have thrown at least 150 pitches this season. It’s the best mark of his career.

His xwOBA (.370) ranked 451st last season.

While McGee isn’t likely to maintain his present home-run suppression marks — the homer he allowed last night brought him closer to his career average — batters are having some trouble squaring him up in part due to location.

Health has allowed McGee to return to his 2015 form but so has curiosity, so has information.