SCOTTSDALE, Ariz. -- Dane Dunning started four of his six appearances last spring, but he broke camp in the Rangers’ bullpen. He went 2-0 with a 1.77 ERA over eight April relief appearances, putting in important innings as Texas raced out to an early lead in the American League West.

But when Jacob deGrom was lost for the season six starts into his Rangers tenure, Dunning was called to the rotation. All he did was turn in the best season of his career. He made the first of his 26 starts on May 5 and provided some stability as the club made the postseason for the first time since 2016, then captured the first World Series title in franchise history.

This spring, Dunning appears to be a lock for the Opening Day rotation, especially with deGrom, Max Scherzer and Tyler Mahle all starting the season on the injured list. Despite that job security and last year’s success, Dunning has talked about adding a pitch to his arsenal, but he’s been cagey about what this new pitch is. Making his second start of the spring on Tuesday against the D-backs at Salt River Fields, where Statcast pitch tracking data is available, Dunning may have let the cat out of the bag.

“It was nice to get an out with the new pitch and not spike it 47 feet, so that was kind of cool, popped him up to center,” he said, referring to Geraldo Perdomo’s second-inning popout on what Statcast called a splitter.

The start was a mixed bag for Dunning, who ended up allowing two runs on two hits with two strikeouts, a walk and a hit-by-pitch in two innings in the Rangers’ 10-3 win. He threw 40 pitches total, 28 in the second inning.

“I got into trouble but worked out of certain situations, made some pitches when I needed to, but I just can’t get myself into those positions to begin with,” he said.

But working out the kinks is what spring is for.

“Get back in the grind, get my legs under me a little more and get the ball rolling again,” Dunning said of his mentality going into his next opportunity.

Manager Bruce Bochy is all for Dunning using Spring Training to experiment with the stuff that earned him a 10-7 record with a 3.55 ERA last season as a starter.

“It’s all about continuous improvement with players,” Bochy said. “You never arrive in this game; you’re trying to get better, and that’s the case with him.”

Leiter looks to rewrite narrative
Rangers No. 5 prospect Jack Leiter made his second appearance of the spring on Tuesday, coming on to start the fourth. He got hit hard in his first inning, giving up a run on four hits, the damage limited by right fielder Evan Carter throwing out Jose Herrera at home on Ketel Marte’s two-out single. Then he put it back together in the fifth, retiring the side on 11 pitches. The outing was emblematic of Leiter’s 2023 season.

The former No. 2 overall pick out of Vanderbilt struggled to a 5.51 ERA over his first 15 starts with Double-A Frisco and ended up shut down for a month on the Developmental List to work on his mechanics and reset. The move paid off, as he posted a 3.31 ERA in his final four starts for the RoughRiders and earned a one-start promotion to Triple-A Round Rock.

• After completing his degree, Leiter has a bigger goal in '24

Bochy called this spring a “clean slate” for the 23-year-old and offered this advice:

“Just be yourself. Go out there and compete,” he said. “Jack, as young as he is, does have a résumé and pitched at a top university being one of the best pitchers in the nation. Go out there and just do your thing, and don’t get too caught up in a lot of the things that some people [outside the organization] may think you need to do.

“Have a good spring here and come out of the spring knowing that you can pitch in the Major Leagues.”

Leiter couldn’t agree more.

“I can only control what I can control, and that’s the task at hand and getting better one day at a time,” he said. “In my head, it’s a clean slate, of course. I did a lot of stuff this offseason and made a lot of progress, and now it’s time to just wait and see if the results take care of themselves.”

World Series rematch, spring edition
Marcus Semien, who homered in the ninth inning of the Rangers’ World Series-clinching Game 5 win on Nov. 1, went deep on the first pitch of Tuesday’s Cactus League rematch with the D-backs. It was Semien’s first homer of the spring in his fourth at-bat.

Backup catcher Andrew Knizner, serving as the DH, added a three-run shot as the Rangers spoiled the D-backs debut of left-hander Eduardo Rodriguez.