Dallas Keuchel’s First Two Starts in the Diamondbacks’ Rotation.

Did Brent Strom make a difference?

Albeit in his first game as a Diamondback Keuchel’s ERA+ was similar to his season average, Dallas Keuchel has the right stuff to be in the Diamondbacks rotation.

It is the track record, it is the reputation that helped him get to this point [to competing for the fifth starter position in the Diamondbacks rotation]. — Torey Lovullo

This season, Brent Strom was the catalyst for improvements by Gallen, Kelly, Bumgarner, and Davies. His magic is already working on Dallas Keuchel. Some advanced statistics in Keuchel’s first start as a Diamondback were amazing (I’ll get to that in a minute).

Because they previously worked together, they immediately got to making adjustments needed for success per Torey Lovullo.

They [Dallas Keuchel and Brent Strom] were able to get right to the important portions of his delivery that would help him get the [better] results that he had [in previous seasons]. —Torey Lovullo

What was amazing about Dallas Keuchel’s first start as a Diamondback?

You would miss ‘amazing’ if you looked at the top level and saw 4 earned runs in 4.1 innings.

His 1.98 Fielding Independent Pitching (FIP) is his career best. His previous best was 2.91 in 2015, when he won the Cy Young.

His 31.8 K% was the highest on the Diamondbacks. That is amazing because Keuchel is known as a low strikeout pitcher (13.2 K% last season).

Weak contact was a strength. Ground balls were weakly hit (82 MPH) with a .148 wOBA.

He kept the ball in the park, allowing zero home runs. Last season he allowed 1.4 home runs per 9 innings.

He doubled his cutters from 17% to 34% per Baseball Savant. This AZ Snake Pit article suggested that he would benefit from more cutters because cutters often result in weak contact.

Hitters were very lucky. Two reasons follow:

• Their BABIP was an unsustainable .500 (6 hits in 12 balls-in-play).
• Their line drive results were 57% better than expected by Statcast (.921 wOBA vs .585 xwOBA). This suggests fielding was less than average.

He discarded his previous goal of getting first pitch swings. In my view this was intentional because 72.7% of his first pitches were outside the strike zone per Baseball Savant. His first pitch swings fell from 30.6% to 18.2%. Perhaps the percentage of first pitches in the zone will vary to keep batters guessing.

“I don’t think we saw him at his absolute best because he was nervous and a little bit up tight [in his first start as a Diamondback]. — Torey Lovullo

“So, we like what we saw [in his first start as a Diamondback]. We want it to continue to improve. We need that guy [Keuchel] to step up.” — Torey Lovullo

What happened in Dallas Keuchel’s second start as a Diamondback?

For a second consecutive start, you would miss ‘amazing’ if you looked at the top level and saw 6 earned runs in 5 innings.

The combination of hitter-friendly Coors field plus two defensive kerfuffles made batters lucky, yet again. The first kerfuffle was in the first inning, when base-runner Kris Bryant ran in front of the throw to second base (it hit his shoulder) preventing an inning-ending double play. Sadly, two batters later a Coors homer happened.

“Walker has the most double plays started of any first baseman in the game, (8), and that was his first throwing error of the year.” — Jack Sommers

“First and foremost he [Keuchel] did his job right there. He got a really good hitter in Blackmon to roll over.” — Christian Walker

The second kerfuffle was in the fourth inning, when Randal Grichuk hit a fly ball between Alek Thomas and Jordan Luplow. It was not caught. Sadly, three batters later a Coors triple scored 3 runs.

“With the quality of outfielders that we have and with that ball being in the air as long as it was. I feel like we should have made a little bit better play on it.” — Torey Lovullo

Coors field reduced Dallas Keuchel’s pitch movement, making it easier for batters to hit the ball.

“His velocity is actually up a couple MPH today, but his vertical and horizontal movement are down...a lot. [The reason was] Coors field.” — Jack Sommers

“Interesting that his velocity is up a notch or two. Coors though may not be the most representative test location, but the DBacks still have to play there, a lot.” — Oldenschoole

“Indeed, Coors was not a representative test. And with any luck Keuchel should have been out of the first with zero runs. ...” — Makakilo

The same as the first game weak contact remained a strength. Although half (9 of 18) of his balls-in-play were ground balls, only one was a hit (a single). His ground ball .205 wOBA was excellent.

The same as his first game, he pitched more cutters (34% per Baseball Savant). Cutters promote weak contact, even at Coors field.

“I thought he threw the ball pretty good.” — Torey Lovullo

Summary.

Dallas Keuchel’s first start as a Diamondback was amazing. His second start might have been amazing except he was pitching at Coors and the Diamondbacks had two defensive kerfuffles. I’d like to see more Keuchel starts.