"It was the first curveball to Gimenez where I felt something kind of twinge," said Adleman, who gave up two runs and three hits over 3 1/3 innings. "I thought, 'All right, maybe it's just a muscle spasm.' It cramped up on me real quick. I threw the second one and it was the same thing."
After being looked at by head athletic trainer Steve Baumann, manager Bryan Price and pitching coach Mark Riggins for several moments, Adleman departed.
"They decided it was probably best to get out of the game, try to get it treated and hopefully try to get on top of it and keep it from being a long, lingering issue," Adleman said.
Reliever Caleb Cotham and an already taxed bullpen had to cover the remaining 5 2/3 innings.
Adleman, who replaced the injured Raisel Iglesias in the rotation late last month, is scheduled to undergo an MRI on Friday to determine the exact severity of the injury. Price acknowledged that it would seem unlikely for Adleman to be able to make his next start.
"The oblique can be, especially if it's significant, a long-term, multiple-week injury that would certainly be a big setback for Tim, and he's been throwing the ball well for us, so a blow to the club as well," Price said.
The Reds' rotation is already missing Homer Bailey, Anthony DeSclafani, Iglesias, Jon Moscot and Michael Lorenzen -- all are on the disabled list because of injuries or setbacks to previous injuries. DeSclafani has also been out with a strained left oblique since late March.
With Adleman likely out, it's murky over who might take his place. The Reds' front office has been steadfast about not rushing top prospects like Cody Reed and Robert Stephenson up from Triple-A Louisville, although Stephenson has been up to make two spot starts already this season. A.J. Morris, who is not on the 40-man roster, has a 2.70 ERA in nine games with Louisville and last pitched on Wednesday.
DeSclafani is scheduled to throw live batting practice on Friday to Reds hitters, but he must go on another rehab assignment before he can return. Moscot is slated to have his second rehab start on Friday for Louisville, but he would have to return on short rest to replace Adleman, which would seem unlikely. He is trying to return from inflammation in his surgically repaired left non-throwing shoulder.
It's an unfortunate break for Adleman, who was making his fourth big league start and is 1-1 with a 3.72 ERA. The 28-year-old's career veered into independent leagues from 2012-14 before he worked his way up from the lower rungs of the Reds' system.
"When you're out there and trying to help the team win and have to come out in the fourth inning, it puts the bullpen and the team in a tough spot," Adleman said. "It's something you can't control, it's frustrating."