Stickiness Is the Key To Zebby Matthews' Success

Zebby Matthews couldn’t have asked for a better start to his MLB career. Despite pitching for the Single-A Cedar Rapids Kernels as recently as May 3, Matthews quickly advanced through the minor leagues and brought his laser-like command to the Show.

His approach of locating his four-seamer along the shadow of the zone and keeping his slider down and glove side ensures he makes few mistake pitches while avoiding walks.

Matthews has even flashed the ability to miss bats, with a respectable 21.0 K% and a 21.7% swinging strike rate (92nd percentile) on his slider.

Although his command is still spectacular, his greatest assets are his slider and cutter. It’s all about stickiness.

Most research shows a pitcher’s Stuff+ and “stuff” is more consistent year to year than location and command. It’s more important to have the right weapons, regardless of whether it’s a flat fastball or a nasty breaking ball. Location is still critical, but pitchers may experience a broader range of abilities throughout their careers.

It’s not true that the best command pitchers are more consistent than the rest of the league. I found the year-to-year correlation of PitchingBot’s command score, botCmd, to be lower for the top 33% of pitchers than the bottom 67%. It’s just one analysis, but the correlation coefficient of the top group was just ~0.3 versus the ~0.45 of the bottom group. 1 would be a perfect correlation, and it would be ideal in this case.

*Data downloaded from Fangraphs. All 100+ inning seasons since 2017, only looking at pitchers with at least two back-to-back years.

Stuff will always be there. Fortunately for Matthews, he has a bit of both.

His slider grades out well, earning a 113 grade from Fangraphs’ Stuff+ model and a 99 from MLBPitchProfiler. His cutter is much the same, earning grades of 96 and 108, respectively.

Matthews’ four-seamer may not compare to the league’s best, but he throws with 70th percentile velocity (94.8 mph) and 74th percentile induced vertical break (16.3”). It’s more than good enough to serve as his repertoire base.

He hasn’t generated much swing-and-miss with it yet, but Matthews’ four-seamer has fallen in for a called strike more than almost any other pitcher. His 26.3% called strike rate is 99th percentile among starting pitchers. As he logs more innings, these rates will balance out. Still, Matthews won’t need his four-seamer to generate whiffs. It’s just fine as it relates to his slider.

Already grading well in stuff, Matthews’ slider is somewhat unique. With just an 8.6 mph difference in velocity (per PitcherList data), his slider has an incredible 17.5-inch difference in induced vertical break (IVB). That figure is a slightly lower 16.6 using MLBPitchProfiler data, but that’s still a massive difference.

Best described by MLBPitchProfiler, Matthews’ slider is a near-perfect example of a gyro slider. He reduces most of the pitch’s spin with a high gyro degree and lets gravity do the rest, as evidenced by his low IVB.

If tunneling becomes an issue and hitters better predict and/or see the difference between his four-seamer and slider, he has a cutter to bridge the gap. Former Twins ace Sonny Gray talked about this last year, and Tyler Mahle also had a cutter with a similar purpose.

Too much difference in movement between the pitches may tip off hitters to what the pitcher is throwing. Mixing in a cutter with a movement profile somewhere between the two may help combat this.

Matthews’ cutter is hard (90.5 mph, 74th percentile), but its IVB and horizontal break sit right between his four-seamer and slider. He can use it to jam lefties or to throw off hitters as he throws it like a second slider. Ideally, hitters won’t be able to track what he’s throwing.

Known more for his command, Matthews’ slider and cutter may better represent his future. It’s not that he’ll suddenly be zapped of his powers, but building a strong base of stuff with his slider, cutter, and four-seamer will ensure prolonged success. He’s already close.