There was nothing rocky about Kumar Rocker's introduction to Triple-A.

In fact, the Rangers' top pitching prospect worked his deepest outing of the 2024 campaign in his Round Rock debut. Rocker -- Texas' 2022 first-rounder, who had a delayed start to his second pro season as he rehabbed from Tommy John surgery -- spun a season-high five innings with a career-high 10 strikeouts in a 4-3 victory in extra innings at Dell Diamond.

Out of the gate, Rocker fired three straight four-seam fastballs of 97.5 mph or more, marking his first outing with public-facing Statcast since the 2022 Arizona Fall League. He struck out Oklahoma City outfielder Drew Avans (Dodgers) on his fourth pitch to begin his punchout line.

Rocker fanned Major League-experienced outfielder Andy Pages and then MLB's No. 39 prospect Dalton Rushing to complete a flawless first. The Vanderbilt product retired the side in order in the second before opening the third with a 101.3 mph comebacker from Alex Freeland (MLB's No. 78 prospect), which deflected off his body to the right side of the infield.

The 6-foot-5, 245-pound hurler initially shook off the line drive and jogged to first base before being checked on by Express pitching coach Dave Borkowski and athletic trainer Will Whitehead. After having his right wrist and forearm looked at, Rocker broke a smile, fired two warmup pitches and stayed in the game.

No one reached base against Rocker the remainder of the night.

• 'It's a show': Rocker's ace potential showing in rehab

The 24-year-old retired the next nine in order, setting down six on strikeouts and punching out four in a row between the third and fourth innings. He fired 44 of his 67 pitches for strikes and got 15 whiffs, a whopping 11 on his slider.

Rocker relied heavily on his slider-fastball mix, as the combo made up 74.6 percent of his arsenal in his ninth appearance of the season. Now just a step from the big leagues, he topped out at 99.9 mph with his sinker and averaged 98.2 on his four-seamer.

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Rocker isn't the only former Vanderbilt flamethrower in the Rangers' plans, though. Jack Leiter -- Texas' No. 4 prospect and 2021 second overall pick -- received his fourth callup of the season Wednesday, pitching in the second leg of a doubleheader, which ended with three runs (two earned) in four innings. Leiter signed in 2021 and climbed the Rangers' ranks to his big league debut this season, but as he struggles to reclaim the consistency that he has had in spurts with Round Rock in his opportunities in The Show, Rocker awaits in the wings.

Starts at the big league level in September could soon have significant competition in the way of two-time Cy Young Award winner Jacob deGrom, who continued his comeback trail for Round Rock on Tuesday. Max Scherzer (right shoulder fatigue) is more of a question mark, while Tyler Mahle's (right shoulder stiffness) return to action is also an unknown.

A two-time first-round selection, Rocker made his latest bid for a big league callup in a mighty way Wednesday. Expected to soon join the Top 100 Prospects list with upcoming graduations, Rocker has been nearly untouchable in his return to full-season ball, as his most recent gem lowered his ERA to 0.36 in 24 2/3 innings between Double-A and Triple-A.