DETROIT -- The Tigers hadn’t even started batting practice when Joey Wentz took the mound at Comerica Park for the first time Wednesday afternoon. First pitch was still three hours away, and the mound was still covered, but Wentz stepped on top and looked around, just to get his bearings.

“It was kind of a depth perception thing,” he said. “It's still 60 feet to the plate and that stuff, more just [for] depth and feel of the mound so my first time out there wasn't my warmup pitches.”

Hours after, as he handed the ball to manager A.J. Hinch and walked to the dugout with two outs in the third inning and six runs in, his view wasn’t nearly as great. At the same time, his spot start in the Tigers’ 9-0 loss to the A’s gave Hinch and general manager Al Avila a good look at another part of their young pitching depth.

Wentz, the Tigers’ No. 12 prospect per MLB Pipeline, showed virtually his whole arsenal in his first at-bat, a 12-pitch battle with Tony Kemp that ended with a walk. The outing that followed gave him lessons to take back to Triple-A Toledo, where he was optioned after the game.

“Every pitch matters,” Hinch said, “and he’s got to dial it in pretty aggressively when he can. If he’s going to get beat, get beat with your best stuff. He’s still got some development left, to be able to spin the ball, get off the fastball a little bit, have the courage to throw some secondary pitches in some fastball counts. And as the game sped up a little bit, he can slow things down.

“He’s a promising young arm," added Hinch. "It’s a good lesson for him. But it wasn’t his night.”

The leadoff walk to Kemp showcased what Wentz brings, and why the Tigers have liked him so much ever since acquiring him from Atlanta in the Shane Greene trade at the 2019 Trade Deadline. His 0-1 pitch was a cutter, a pitch he developed a few weeks ago with Mud Hens pitching coach Doug Bochtler. From there, he threw a 93 mph sinker for the only swing and miss of the at-bat. He followed that with a 96 mph fastball, showcasing the velocity jump he has posted since rehabbing from Tommy John surgery two years ago.

Kemp fouled off the 96 mph heater, then laid off the 76 mph curveball. He fouled off a 94 mph sinker and the 83 mph changeup that followed.

“I felt like I threw him everything,” Wentz said. “I was scanning the scoreboard for a pitch counter, but I couldn't find it. I knew it was a lot.”

From there, Wentz attacked him with a barrage of fastballs. Kemp fouled off the three in the zone and took the two that weren’t, drawing the walk.

“It’s a little bit of a bummer that raises the pitch count right away,” catcher Tucker Barnhart said. “He grinded and grinded and grinded. Good at-bat by him.”

Wentz nearly got out of the inning unscathed thanks to a rundown that caught Kemp between third and home. However, Chad Pinder moved to third on the play. Wentz had an 0-2 count on Sean Murphy, a pitch away from escape, and got him to chase a changeup off the plate. But Murphy got enough to send a blooper into center for an RBI single.

Wentz got some measure of revenge by reaching behind his back to snare Ramón Laureano’s comebacker despite its 102.5 mph exit velocity, but it was his 30th pitch of the inning. Christian Bethancourt’s single through the middle on his first pitch of the second inning put him back on the defensive.

From there, the outing unraveled -- six hits in an 11-batter stretch, four of them line drives into the gap. Wentz’s command wavered; he threw first-pitch strikes to only one of his final eight batters after getting ahead on seven of his first eight.

“I thought we could’ve done maybe a little bit better job getting ahead,” Barnhart said, “but in my opinion, you can’t put too much stock in a debut. It’s a tough thing to do, to try to keep your emotions intact. He’s pretty stoic, but I’m sure his heart was racing.”

Wentz summed up what he was missing in one word: Quality.

“I think my raw pitches play,” he said. “I think that where they don't play is over the dish and belt-high. I haven't really watched the video on it, but I'm assuming there's a lot of that today and a lot less of the corners and down and up. I thought I did have some good pitches, but overall the quality just wasn't where it needed to be.”