BALTIMORE -- Back in the big leagues for the third time this season, Orioles pitching prospect Cade Povich looked a bit different when he took the mound Saturday at Camden Yards.

The 24-year-old left-hander didn’t wear his typical long, baggy pants. He instead wore high black socks. Povich even changed his warmup song, preparing for his start to the notes of “Piano Man” by Billy Joel. (He wanted to incite a singalong a la Gunnar Henderson’s “The Sweet Escape,” and it was successful.)

Then, Povich started aggressively attacking the strike zone -- much more than in the past -- which proved to be the key to his career-long 6 1/3-inning gem during Baltimore’s 5-1 loss to American League East rival Boston.

This wasn’t the same Povich from his previous eight starts for the O’s earlier in the season. This wasn’t even Cade Povich.

This was “Slim.”

“Different kind of alter ego,” said Povich, the Orioles’ No. 5 prospect per MLB Pipeline. “I think the other games were Cade, and I went down [to Triple-A Norfolk] and talked to some people, mental stuff. Some of the guys down here call me, 'Slim,' so I kind of took that attitude into this game. Different mindset, different person. Someone that's just going to be aggressive and attack early and as long as I’m in the game."

This version of the 6-foot-3, 185-pound Povich -- making the nickname “Slim” an appropriate one -- could factor into Baltimore’s pitching plans for the rest of the season. However, he was informed after Saturday’s game that he is being sent back down to Triple-A, according to a source.

Still, Povich made the most of his latest big league opportunity, which he was presented with because the Orioles wanted to give all of their starters an extra day of rest this turn through the rotation. Povich capitalized in an impressive manner.

Not only did Povich work into the seventh for the first time in the big leagues, but he was much more efficient while retiring 14 of the first 15 Red Sox batters he faced. He threw 30 strikes and only nine balls over the first four innings.

The seven previous times that Povich pitched at least four innings for the Orioles, he needed 64 or more pitches to get through the fourth.

“I thought he had a really good changeup,” manager Brandon Hyde said. “I thought he was ultra-aggressive in the strike zone. It was great to see him throw multiple pitches for strikes and really attacking them. That was awesome to see.”

While collecting a career-high-tying six strikeouts and not issuing any walks during the 89-pitch outing, Povich induced a good bit of swing-and-miss with all four of his offerings. He generated five whiffs with his four-seam fastball, four with his changeup, four with his curveball and two with his sweeper.

Povich finally faced some trouble in the sixth -- when the Sox rattled off three singles, including Tyler O’Neill’s knock that broke a scoreless tie -- but he limited the damage. Povich stranded a pair of baserunners by inducing back-to-back flyouts, completing six innings for the second time in the bigs after previously tossing six scoreless frames on June 12 vs. the Braves.

“First time seeing a guy, you never know what to expect. He’s got pretty good stuff,” O’Neill said. “He’s got a good breaking ball and a few different pitches you have to think about.”

The O’s didn’t give Povich much support. Their lone run came on a homer by Gunnar Henderson, who belted a two-out solo shot in the sixth that ended a no-hit bid for Boston right-hander Brayan Bello.

Povich took the loss, as he left with a runner on first base who later came around to score on Jarren Duran’s go-ahead two-run single off Yennier Cano. So Povich was charged with two earned runs allowed.

However, prior to that, Povich received a deserved standing ovation from the orange-clad crowd after a tremendous performance.

“That crowd, I had the chills coming off a little bit,” said Povich, who had a 6.27 ERA over his previous eight MLB starts. “Still kind of in game mode, but I guess a little bit trying to fight off a smile. It was special.”

Povich will likely return to the big leagues before the end of the season. Baltimore’s rotation is already banged up, and injuries could occur at any time. Plus, rosters will expand to 28 players on Sept. 1. Maybe Povich could even provide a boost to the bullpen as the O’s seek their second straight AL East title down the stretch.

Whenever Povich’s name is called upon again, he’ll be ready.

And so will “Slim.”