Mulder was pulled in the first inning of Wednesday night's game against the Phillies at Citizens Bank Park when he encountered further trouble in the left shoulder that has bothered him for more than two years.
He felt pain in the joint on his eighth pitch, a fastball that struck out Jimmy Rollins, and was unable to get normal extension in his arm after that. He threw eight more pitches, all of them balls, before calling head athletic trainer Barry Weinberg out to the mound.
"It was just on the one throw," Mulder said. "But after that one throw, I couldn't get my arm back up. Couldn't get it to work right."
General manager John Mozeliak said after the game that the club expects to place Mulder back on the disabled list for the fifth time in his four seasons in St. Louis. Moreover, Mozeliak acknowledged that Mulder's attempts at a comeback in a Cardinals uniform appear to be at an end.
"He's just not getting over the hump," Mozeliak said. "Typically, I have a very optimistic tone. But in this case, it's hard to envision this getting to a point where it's going to work for us or for him."
St. Louis expects to call up left-handed pitcher Jaime Garcia from Triple-A Memphis. Garcia has pitched as a starter but will be used out of the bullpen in St. Louis. The club expects that Garcia will be able to make it to Philadelphia in time for Thursday afternoon's game.
It was another discouraging turn in a long and frustrating saga for Mulder. He was making his first Major League start since Sept. 16 of last year, and his fifth since June 20, 2006. In the past two years he has undergone two shoulder operations.
Each time the primary issue has been the same. Mulder has been consistently unable to get his throwing arm into the proper position to release the ball. A newfound lower arm slot seemed to have solved the problem, but on Wednesday the same problem cropped up yet again.
"That's the biggest frustration," he said. "It just keeps teasing you and you keep getting let down and don't really know what to do."
Mulder came out throwing fairly hard and looking good. He hit 90-91 mph on his fastball against Jimmy Rollins. But the eighth offering, a ball Rollins took for a called third strike, felled Mulder's chances of a successful night.
"They were throwing the ball around, and I was walking around the mound just kind of waiting for it to go away, and it started to," he said. "It started to go away. But after that I couldn't throw right. It wouldn't let me.
After his last pitch, a ball to Chase Utley, veered well out of the strike zone, Mulder indicated something was wrong. Weinberg and manager Tony La Russa came to visit Mulder, and he was removed from the game.
"It started to go away and I didn't feel it on those other pitches, but there was nothing I could do at that point. I had to call them out. It was like my body wasn't going to let me feel that again."
Matthew Leach is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.