PHILADELPHIA -- A chocolate shake was waiting for Colin Holderman back at his Citizens Bank Park locker Thursday night. He’s not a huge post-game meal person, but on this night he asked head Major League dietician Hillary Ake for something sweet after the game.

"I'm not really as hungry after an outing, but I need to keep this weight on somehow,” Holderman said.

Baseball is a game of numbers, and right now, one of the ones Holderman is monitoring closest is his weight. In Spring Training, he caught a flu strain that ran through the Pirates’ clubhouse. Normally, the 6-foot-4 right-hander weighs about 235 lbs. In just a couple of days, he was down to the 216-217 range. He hadn’t played at that since he was in A-ball.

“I saw my abs for the first time in a very long time and I told my wife, ‘Take a picture cause you might not see these ever again,’” Holderman joked at his locker at Citizens Bank Park Thursday. “That was the only positive for losing that weight.”

On Thursday, Holderman was activated off of the 15-day injured list and made his season debut, throwing two-thirds of an inning in the Pirates’ 5-1 loss to the Phillies.

A miscommunication between Michael A. Taylor and Edward Olivares in right-center resulted in an error, and Bryson Stott homered two pitches later to put the game effectively out of reach. That came on the heels of Jared Jones tossing another quality start -- the seventh straight for this rotation -- but his night ended on a sour note thanks to a two-run homer by Brandon Marsh.

For Holderman’s first outing back, his fastball sat in the 96-97 mph range while his breaking stuff was consistent with its 2023 form in terms of spin and horizontal movement.

"Felt strong out there,” Holderman said. “It's not the velo that I had last year early in the season. I was down 96, 97 last year as well. As the season builds, hopefully that goes with it. I felt really good."

Manager Derek Shelton downplayed the home run in his assessment of Holderman’s first outing of the season, praising that he went out there and threw strikes.

“Overall, he looked healthy and the ball came out well," said Shelton.

It may not have been the optimal first outing Holderman wanted, but it sure beats being sick in bed. His spring training illness was serious enough that he had to be hospitalized, and he knew well before the final roster crunch last month that he was going to have to start the year on the shelf.

“Never been that sick before and hopefully never again,” he said.” That was miserable.”

Holderman isn’t quite back up to his pre-sickness weight, but the team could certainly use another big arm in their bullpen right now. Closer David Bednar has not been sharp out of the gate, lefty Ryan Borucki is on the injured list and Carmen Mlodzinski just had his rehab assignment end and was optioned to Triple-A Indianapolis on Wednesday. The team really could use a right-handed power sinkerballer, and they have one again.

Not to mention that Holderman was itching to get back watching his team jump out to their hot start. Even after their loss Thursday, the Pirates are still 9-4.

“You see how well they’re playing and how everyone is throwing the ball, it’s tough watching from Indy, or even in Florida when I was there,” Holderman said. “It’s awesome to be back with the boys. The vibes are high and hopefully we can keep this going.”

In Spring Training, Holderman was aiming to be the seventh- or eighth-inning guy again, the role he had for most of 2023 when he pitched to a 3.86 ERA over 56 innings. He has the stuff to pitch in that type of role, and assuming he and Bednar regain their 2023 form, they and Aroldis Chapman could form a formidable backend of the bullpen.

“Those last three [Minor League outings] definitely gave me the confidence to say I’m ready to be back, that my stuff is there and my command is there,” Holderman said. “I’m excited to show it off on the big stage.”