Five days after pitching in the All-Star Futures Game in Phoenix, MLB.com's No. 50 prospect made his Double-A debut in Harrisburg on Friday, allowing a run on three hits over 4 2/3 innings as the Akron Aeros beat the Senators, 4-3.
Pomeranz, for whom control was a concern coming out of college, struck out five and walked one while throwing 91 pitches.
"I felt a little rusty in the beginning, just not throwing all that much during those days when we had the Futures Game," he said. "I got into a few deep counts, they fouled off a lot of balls.
"I wish I could've gone deeper into the game, but overall I was pretty happy with my performance. I threw a lot of pitches but only had one walk. For the most part, I threw all three pitches for strikes. It felt good to go out there and get that first Double-A start under my belt."
The 22-year-old left-hander retired the first six batters he faced, striking out three, before serving up a leadoff homer to Archie Gilbert in the third. He turned out to be the only Senator to get past first base against Pomeranz.
"I got in a deep count and he's dead pull hitter," Pomeranz said. "I was pounding fastballs into him and he finally just got one."
The University of Mississippi product twice faced Bryce Harper, the top overall pick in the 2010 Draft, striking him out both times. MLB.com's No. 2 prospect finished the game 0-for-4 with three strikeouts.
Pomeranz, who was drafted four picks after Harper, said he doesn't focus too much on who's in the batter's box.
"He's just another batter," he added. "I try not to even look at the hitter too much because he doesn't even matter. It's just me and the catcher. I'm happy I struck him out twice."
Pomeranz started the season with Class A Advanced Kinston, where he led the Carolina League with a 1.87 ERA and struck out 95 batters in 77 innings. K-Tribe manager Aaron Holbert told him last week he'd been promoted.
"I found out last Friday, the day before I left for the Futures Game," Pomeranz said. "I was happy. I'd been wanting to get moved up, but there was nothing really I could do about it. They felt I was ready, so I was happy they felt I was ready to get moved up."
To carry that success into the Eastern League, he'll have to keep improving in the same areas he worked on at Kinston, Pomeranz said.
"Throwing three pitches for strikes and trying to get ahead of hitters so I can keep my pitch count down and get deeper into the game. ... Just building on those things," he said. "Being more efficient, getting ahead, throwing any pitch in any count. Things will work out well for me if I'm doing those things right."