ARLINGTON — Kumar Rocker has pitched into the seventh inning of a big league baseball game by now, yeah?

Nah.

So the last time he did it was, what, in some minor league game?

Nope.

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OK, so, it happened during his brief stint with the independent league Tri-City Valley Cats, right?

Try again.

“The last time I did that was in college,” Rocker said Wednesday night. “It was probably my junior year, my draft year.”

Bingo. Rocker, the Texas Rangers’ electric rookie right-hander, threw into the seventh inning of a game on June 6, 2021 vs. East Carolina in game one of the NCAA Super Regionals and didn’t do so again until Thursday vs. the Los Angeles Angels. The 26-year-old threw seven innings of three-run ball to earn his first major league win, anchor a 5-3 victory and secure a series sweep at Globe Life Field.

“Going out there for the seventh,” Rocker said before he cracked a grin. “I was like, this is cool.”

His start vs. East Carolina four years ago was Rocker, a dominant force at Vanderbilt, at his peak. His start Thursday vs. the Angels was Rocker, a tantalizing prospect with room to improve, at his best as a big leaguer. It exemplified his growth and, in turn, the state that the Rangers’ pitching staff. The Rangers’ rotation has an American League-best 3.17 ERA and Rocker, whose stuff is high class, is only just finding his form.

If he can find it on a consistent basis?

Watch out.

“It shows he can do it,” Rangers manager Bruce Bochy said. “He knows he can do it. He can do it again. That’s a great way to get your first win and go seven innings too. We were all happy for him with how he threw the ball. He’s got the stuff to be a really nice major league pitcher. He can be a dominant one and he showed that tonight.”

Rocker’s dominance — which included eight strikeouts, no walks and just 78 pitches — was keyed by the reemergence of the hard slider that helped rocket him up prospect rankings this winter. Rocker threw a career-high 45 sliders vs. the Angels, generated a dozen swings and misses with it and used it on six of his strikeouts.

He’s struggled to find the command and comfort of his slider since the start of spring training and batters hit .391 against it in his first three starts this season. He threw it just five times in his last start against the Seattle Mariners and favored his curveball as an off-speed offering to pair with his fastball. On Thursday, Rocker said, it felt the best it’s felt “this whole year” and he decided to amp up the usage.

“It’s been a process to find it,” Rocker said. “It’s hard to find it up at this level. I got lucky, blessed, whatever you want to call it.”

Rocker allowed a run in the first inning after Taylor Ward clubbed a leadoff double and Jorge Soler drove him in with a single. He gave up two more in the fifth when the Angels dinged him for three singles and a fielder’s choice. Rocker struck out Angels right fielder Mike Trout — for the second time Thursday night — with a high 96.1 mph fastball to strand two runners on base.

He turned it over to the bullpen in the eighth inning. Veteran right-hander Chris Martin, who was unavailable Wednesday night with hip discomfort, struck out two batters in a perfect inning. With regular closer Luke Jackson down after he pitched on back-to-back nights, Bochy turned to left-hander Robert Garcia, who’s stepped into a high-leverage role in his first season with the team.

The 28-year-old, whom the Rangers acquired from the Washington Nationals in exchange for Nathaniel Lowe, needed just five pitches (each of which were strikes) to retire the side in order and earn his first career save. He’s the third different reliever to record a save for the Rangers this season and has been a key cog in a revamped bullpen that’s strayed away from meltdowns for the balance of the year. The relief staff’s performance (3.82 ERA) is league average; it’s still a significant improvement over the last two seasons, and when paired with a top-line rotation, it’s effective.

“I said we would be fluid down there with how he would use those guys,” Bochy said. “He showed he can handle that. He wasn’t in awe of anything. He looked the same. It’s nice to have some guys that we can mix up and give guys days off to fill in there.”

It’s a luxury that the Rangers haven’t always been able to employ during Bochy’s tenure. The same can be said about a No. 5 starter who can pitch seven innings with a premier arsenal that rival’s the game’s best.

If night’s like Thursday can become commonplace?

Yeah, watch out.

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