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Breaking down Brad Keller’s Opening Day start

Did Brad Keller give us a legitimate threshold for his performance in 2019?

MLB: Chicago White Sox at Kansas City Royals Peter G. Aiken

An Opening Day, Brad Keller was everything a staff ace should be. He went seven innings, gave up two hits with one walk and five strikeouts. Out of the 92 pitches he threw, Keller went to his four-seam 38% of the time, slider 33%, and his sinker at 29%. That’s an excellent pitch spread but you could make a case to lump the two fastballs together (four-seam/sinker) for a 71/29 percent ratio. For me, the pitches behave differently so they are their own separate entity regardless of velocity ties.

Keller was pretty dominant at times Thursday afternoon. Both fastballs were used mainly early in counts, generally with even split between the four-seam and sinker. A disparity would occur when Keller fell behind the hitter, which he then relied heavily on the four-seam.

The pitch was pretty effective for him. Keller didn’t allow a hit (7 BIP) with the four-seam and drew fouls (12) on three out of every five swings. His control with the four-seamer appeared pretty good as well, with just a 25% non-strike rate. However, he didn’t miss many bats with the pitch either- just one whiff.

That singular whiff could be considered troublesome but it seemed the fouls he generated on the four-seam were due to the hitter’s timing being off rather than missed opportunities on bad pitches.

And that lone whiff accounted for one of Keller’s five strikeouts. I mentioned the importance of keeping his four-seam elevated in an article I wrote for Pitcher List during spring training. The fourth pitch of the at-bat saw Keller deliver a slider low and inside. Keller then built off that with fastball up and away for strike three.

That 95 MPH fastball had a spin rate of 2378 when he struck out Daniel Palka. The above average velocity and spin rate caused a slight ‘rising’ effect which further created deception for Keller. I say deception because I’m sure Palka was expecting a sinker (they both have similar initial movement) as evidenced by his swing that was well under the pitch.

Clearly his bread and butter, Keller’s sinker yielded slightly different results. He allowed just a walk and a single, neither of which proved to be problematic.

Keller is a high ground ball pitcher (and that’s thanks in part to the sinker as well) and when the slider was put in play, half of hitter’s contact was driven into the ground. Keller mainly used the slider later in counts, especially when he got ahead/had two strikes on right-handed hitters. Keller also threw it as his first pitch a few times, but mainly to left-handed hitters.

Four of the five strikeouts Keller got against the White Sox were from the sliders in the super cut below.

Keller’s slider was pretty good last year but its shown marked improvement so far. He’s made several adjustments with the pitch, mainly the spin rate and the axis of rotation.

The spin rate on his slider during his first start of 2019 saw an improvement of 122 RPMs. In 2018, he averaged 2470 RPMs on the pitch but it jumped to 2592 RPMs last Thursday. The significance of the elevated spin rate can be helped by the fact that Keller is also throwing the pitch a half a mile an hour faster (85.6 MPH vs. 86.1 MPH).

Spin rate and velocity work together to create movement thanks to the way the slider ‘works’ with gravity. The degree of spin also contributes to the manner with which the pitch breaks. Having the higher velocity and spin rate allows the pitch to hang just a little bit longer than normal before it drops off the table like in the examples above.

Keller also has adjusted his spin axis this year by about 16 degrees from his 2018 average (71.1 degrees).

Those three improvements have allowed his slider to break and extra inch vertically and an additional half inch horizontally. That matters because with his improved pitch metrics on his fastball, he’s creating extra distance between the two pitches (roughly an extra two inch separation both horizontally and vertically). And that’s great news for Keller because it creates an even better tunneling situation for him.

Despite whatever changes Keller may have made to the proclivity of his pitches, his release points remain very tight. This is going to create a tremendous amount of deception for Keller when he uses his fastball/slider in tandem.

As I suggested in my aforementioned article, Keller should keep his four-seam elevated to play better off his slider. I tweeted an example of this a few days ago.

And it looks as though Keller kept his four-seam up for the most part.

The sinker and its arm-side ride and break should be sprinkled in to keep hitters true so they can’t just sit on his four-seam fastball.

Keller couldn’t have done a better job than he did Opening Day. We have to remember that expectations have to be tempered this early in the season while also keeping in mind that (and I mean no disrespect, Chi-town) the White Sox are a pretty average team at this juncture.

Keller appears to have done the right things to become a better pitcher, albeit through just one start. Can it be sustained? He’s going to have some ups and downs as the year rolls on but I think we are going to see a lot more positive than negative outcomes, especially if the third highest-scoring offense in spring training can keep scoring runs.