Caleb Ferguson is succeeding with a single pitch

Caleb Ferguson’s MLB career got off to a rough start. He allowed four runs in 1⅔ innings in Pittsburgh and it looked like he wasn’t ready for the gig.

But he persisted and made a couple more starts that went better than his first. Some of the veteran starters got healthy and that pushed Ferguson to the bullpen. He has thrived in the role, posting a 2.31 ERA, 3.04 FIP and a 27.3 K-BB% as a reliever. His first eight outings out of the bullpen saw him log 20 innings. His next 15 saw him log 15⅔ innings. His role has changed even while pitching out of the ‘pen.

Armed with a fastball, curveball and changeup, Ferguson has been doing most of his work with the 4-seamer. This is a bit odd because the scouting report on him coming up through the minors always had his fastball as more of a sinker-type that produced grounders at a 59 percent rate in 2016. Something changed in 2017 that saw his ground ball rate fall to 45 percent. Conversely, his strikeout rate has increased in every minor-league season of his career.

Ferguson has traded grounders for strikeouts, which isn’t a bad thing. In the majors, he has seen his strikeout rate and ground ball rate increase to 29.5% and 45.4%, respectively. That’s good! Hopefully it’s a trend that continues. What has me really interested about his profile is his fastball — specifically, his strikeout numbers with it.

He has a really good fastball ... and that’s about it. Sure, he has a curveball and changeup, but they’re not refined offerings. His curveball is the 15th-lowest in baseball in FanGraphs’ pitch value statistic at -1.8 among relievers with 30 innings pitched. His changeup has fared much better (+0.1), but he only throws it 3.1 percent of the time, so it’s a victim of small sample size.

His fastball is his bread and butter. He throws it nearly 72 percent of the time at an average of 93.8 MPH. According to Baseball Savant, he has the 15th-best whiff rate on fastballs among all pitchers. That puts him in the same company as Orioles’ reliever Mychal Givens and Mariners’ ace James Paxton. But as a reliever, his whiff rate isn’t as great (just 36th-best among relievers).

Ferguson’s fastball is a mystery. The data doesn’t really show his fastball should be as successful as it is. He doesn’t have elite spin rate (it’s slightly above-average). It doesn’t move at an excessive rate (either horizontally or vertically). Because it lacks elite spin and truly elite velocity, I’m not sure how he gets so many whiffs on the pitch.

Baseball Savant

Hitters don’t really chase the heater and he lives in the strike zone with it. But at least he’s consistent. His horizontal pitch location has been virtually the same all season.

Brooks Baseball

Whatever he’s doing is working. He has a .288 wOBA and a .279 xwOBA (expected weighted on-base average) against his fastball this season, good for 80th- and 31st-best among all MLB pitchers.

In September, Ferguson has started to pitch up in the zone with his fastball, and is has led to his second-highest whiff rate of the season on the pitch. It’s still not a chase pitch, but somehow, some way, he has been effective with it. Perhaps this trend will continue.

If the best thing that can be said about it is he misses bats with it and limits the exit velocity, that’s not a bad thing. It’s just odd that the numbers don’t definitively prove why it has been so successful.

For him to succeed in the long run, he’ll have to either improve one of his existing pitches or add to his repertoire (cutter? slider?). But his rookie season has been a surprisingly good one and he has become one of Dave Roberts’ most trusted relievers. The future is bright for Ferguson.