Diamondbacks’ Ryne Nelson rejoins rotation vs. Cubs after Triple-A adjustments

PHOENIX — Rookie right-hander Ryne Nelson will get the nod for the Arizona Diamondbacks on Thursday at the Chicago Cubs, rejoining the rotation from Triple-A Reno, manager Torey Lovullo announced on Wednesday.

The D-backs opened a spot in the rotation when they optioned Slade Cecconi on Monday, and Nelson slotted in ideally after pitching Saturday for the Aces.

The 25-year-old was optioned on Aug. 13 after a pair of short starts. The idea was for him to find consistency with his offspeed arsenal.

“There’s been a lot of work done on his slider primarily, his offspeed pitches. His last outing was much better,” pitching coach Brent Strom said.

“Hopefully this, much like with (Brandon) Pfaadt), time around will be better. I’m looking forward to seeing him again. The reports have been pretty good.”

Nelson has thrown 17 innings over his last three starts in Reno and allowed five earned runs with eight strikeouts. He forced 10 whiffs on Saturday, mostly with the cutter.

He will slide into the rotation during a critical series against a fellow National League Wild Card contender and one of the top scoring offenses in baseball since the start of July.

Ryne Nelson, K'ing the Side. pic.twitter.com/RkvVJZItnl

— Rob Friedman (@PitchingNinja) April 21, 2023

Ryne Nelson’s adjustments

Strom said the reports on Nelson’s slider have been positive, that he’s throwing it a bit harder and making fewer mistakes. It’s a pitch he’s used to miss barrels but has struggled to throw for strikes or create whiffs in the bigs.

“Here’s the deal. So a lot of times young pitchers come into an organization, especially when you have a really good fastball like he has. … They come in blowing 97-98 mph. And if you do that through high school and college, is there a need for breaking ball? Do you develop your skills? Probably not as much as you should,” Strom said.

“When you’re me as a young pitcher and you don’t have that kind of fastball, you develop your breaking ball and then add to the fact. … The older you get, the more difficult it is to teach this stuff.”

Nelson was the only D-backs young starting pitcher who did not spend time in the minors this season until his option. His results have varied throughout his rookie campaign after he received a cup of coffee in 2022.

His April ERA was 6.39, but he stabilized in May and June with a 4.10 ERA and 4.13 FIP.

He had a couple gems in that span, including seven innings of one-run ball against the San Francisco Giants at Oracle Park. He allowed one run in 7.1 innings in his first July start against the Los Angeles Angels in which he struck out Mike Trout and Shohei Ohtani twice.

Masterclass performance starring Ryne Nelson.

7.1 IP, 3 H, 1 ER, 1 BB, 6 K pic.twitter.com/3P7Ltdjyu0

— Bally Sports Arizona (@BALLYSPORTSAZ) July 2, 2023

His peripherals in July fell off (6.35 FIP) with a significant decrease in strikeouts and an uptick in slug. Overall, he is in the bottom 10 percent in the majors in strikeout rate (15.2%) and whiff rate (19.6%).

Strom said he evaluates a pitcher’s peripherals and pitch sequencing when they are down in Reno.

He harped on the importance of speeding up and slowing down hitters, which he called part of the evolution of learning to pitch.

“You constantly have to reinvent yourself not only from game to game, but sometimes from at-bat to at-bat,” Strom said.

He gave an example of Cecconi struggling to do so during his start against the Baltimore Orioles on Sunday that led to his demotion.

Bryce Jarvis down

The D-backs optioned right-hander Bryce Jarvis to make room for Nelson, eliminating a long reliever from the bullpen after he threw two scoreless innings in Wednesday’s 12-5 victory over the Colorado Rockies.

Jarvis, a 2020 first-round pick, came up on Aug. 13 and has a 2.81 ERA and 1.06 WHIP in 16 innings with the Diamondbacks. However, he allowed earned runs in four of seven outings.

“We felt like he was more protection and guarding us in a situation where we needed some coverage for length to allow us to preserve some of our pieces,” Lovullo said. “We feel like we’re keeping the best parts that will help us win games. And that’s got to be our mindset.”

Jarvis was drafted as a starting pitcher, and he transitioned to the bullpen weeks ahead of his call-up to help with Arizona’s depth.

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