BRADENTON, Fla. -- Casey Mize not only was staring at a 6-foot-6 catcher as Grayson Greiner walked to the mound, he was staring at a potential hook.

Mize's first four batters Sunday churned out back-to-back doubles, a nine-pitch walk and a tough-luck bloop single that fell where a shortstop would normally be. His adrenaline was flying like his fastball. Due up was the middle of the Pirates' order, starting with Colin Moran and Gregory Polanco.

“Just some fastballs early that I didn’t command very well,” Mize said after the Tigers’ 8-4 split-squad win at LECOM Park. “And really, that’s the story with me often: If I don’t command the fastball very well, I’m going to give up some hits.”

Fifteen pitches in, Mize was looking for his first swing and miss. Will Vest, his Double-A Erie teammate from last year, was warming in the bullpen.

“I was on the top step [of the dugout],” acting manager Lloyd McClendon said. “I like my job. He was coming out, trust me.”

Mize didn’t need to light up a radar gun or buckle a batter’s knees. He needed outs any way he could get them.

“The single was on a cutter in on his hands, and we were shifted,” Mize said. “So honestly, it probably just [ticked] me off, and then I just decided, ‘Hey, I need to get these guys out.’ So I went back to the bread and butter and started throwing more splitters.”

The splitter is the pitch Mize built his top-pick resume on at Auburn. Of the few people in the Majors who throw it, nobody throws it like Mize.

“I caught a few of his bullpens early in camp, and he was searching for his splitter a little bit,” Greiner said. “He threw his first one [today] and it was filthy. …

“It’s not a very common pitch. The one he had today was devastating.”

Moran swung and missed at two splitters in a four-pitch strikeout. Polanco whiffed on another before fouling out to third.

With McClendon looming, Mize threw just three fastballs in his final 12 pitches. Two fastballs went to cleanup hitter Will Craig, a friend of Mize. The first one actually hit him, but he swung at it.

“He’s a buddy of mine, and I hit him in the hand,” Mize said. “I feel bad about it, because it was not a foul ball. It hit him square.”

Four pitches later, Mize threw his best fastball of the day, 95 mph on the outside corner for a called third strike. A near disaster of an outing became a reminder of how good the Tigers’ top prospect -- and No. 7 in baseball, per MLB Pipeline -- is.

“With a little seasoning and smoothing out the edges, he’s going to be pretty darn good,” McClendon said.

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Despite a two-run inning, Mize could walk away with a good feeling. But his Erie teammate and fellow first-round Draft pick, Alex Faedo, was due to pitch in a couple of innings. So Mize stayed in the dugout for three more frames.

“I just wanted to see him, man,” Mize said. “It’s cool to be able to watch these guys compete, and Alex is an ultimate competitor. He’s a goofball, but when he’s out on the mound, that guy competes his tail off.”

Faedo, too, had some jitters. His first batter, Charlie Tilson, drilled a liner that Derek Hill ran down in right-center before JT Riddle tripled into the corner. Faedo went to his out pitch, the slider, to strike out Moran before using a 94 mph fastball to retire Polanco.

“First-game rust. I threw more balls than I’d like to,” he said. “But overall, I was happy to get a zero and give us a chance to win.”

Faedo tossed 1 1/3 scoreless innings with two strikeouts. As he did his post-outing work in the clubhouse, he received a text from fellow prospect Matt Manning, who tossed two innings with an unearned run allowed in the other split-squad game -- a 5-1 win against the Braves.

“The guys all like to pull for each other,” Faedo said. “We just want everyone to do good.”

All in all, the kids had a good day.