MESA, Ariz. -- Eerie Halloween music emanated from the Sloan Park speakers following batting practice on Monday afternoon, a precursor to the terror that would be trying to hit against Kumar Rocker during his fifth Arizona Fall League start.

The third overall pick from the 2022 Draft spun his best performance as a member of the Saguaros, striking out five over three scoreless innings. The lone blemish on his ledger was a single in the second, which he deftly worked around by striking out the next three batters. The Rangers’ No. 8 prospect peppered the strike zone, with 30 of his 45 pitches going for strikes in Surprise’s 5-0 win over Mesa.

The 6-foot-5 right-hander consistently sat at 95-96 mph with his fastball, while he worked in mid-80s changeups and sliders. Rocker’s slider, which grades out as his premier pitch per MLB Pipeline (70, on a 20-80 scale), was sharp and utilized with frequency Monday.

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“I was trying to establish the fastball and the slider came along with it, so it worked out well,” Rocker said.

The five strikeouts compiled by the righty came on a variety of pitches: two on the heater (one swinging, one looking), two on his breaking ball and one on the changeup. A power-packed Solar Sox lineup -- which included two Top 100 prospects (Jasson Domínguez and Zack Gelof) and Matt Mervis (Cubs No. 21), who is tied for the AFL home run lead -- was entirely flummoxed by Rocker’s pitch mix.

Calling the game as part of Surprise’s starting battery was catcher Henry Davis (Pirates No. 1), with the two working seamlessly in tandem. Numerous Saguaros players have spoken highly of Davis’ zeal behind the dish entering contests throughout the fall.

“He comes into the game prepared,” Rocker said of Davis. “I trust him and he brings a different intensity to the game. He did a great job today.”

Prior to arriving in Arizona, Rocker’s only in-game experience this season came as a member of the Tri-City Valley Cats of the independent Frontier League. While he dominated in a five-game stint on that circuit, the layoff between time on the mound can be difficult for any hurler to counteract.

Through Rocker’s first four fall circuit turns, he amassed nine walks over 7 2/3 innings. While command has never been his premier tool, the sharp increase in a small sample size is peculiar for a pitcher who averaged just 2.6 BB/9 across three seasons at Vanderbilt. After his zero-walk start Monday, the righty cited a desire to keep things simpler moving forward and to continue his learning process.

Rocker was a prime candidate to join Surprise for a spell due to his time away from competitive in-game action. Texas rolled the dice on the 2019 College World Series Most Outstanding Player after he went unsigned following his selection as the 10th overall pick in ‘21 by the Mets due to medical concerns surrounding his right shoulder and elbow. The Saguaros have slowly ramped up his pitch count over the past month, while the 22-year-old has worked closely with the coaching staff.

“Our pitching coach has been great -- Julio [Pimentel, a coach in the Royals organization] -- he knows the vibe of the guys every time we show up to the park and he’s there to make great adjustments for us,” Rocker said. “He’s been a great resource to use here.”

Pimentel has overseen a Saguaros staff that boasts far and away the best team ERA in the league, nearly a point lower than the next closest club (Peoria). Rocker’s three dominant frames set the stage for Surprise to spin its second shutout of the season with five relievers -- including Rangers left-handed prospect Grant Wolfram -- adding scoreless appearances.