Mulder, mired deep in one of the worst slumps of his career, complained of an inability to get full extension of his left arm. When the condition did not improve -- and with a need to remove a pitcher from the roster in order to make room for Reyes -- Mulder went on the DL.
"I can't get my arm up," Mulder said. "It's pretty obvious when you watch me pitch. So I'll go back tomorrow and see what's going on."
Mulder will return to St. Louis on Friday. At that time he will be examined by Dr. George Paletta in an attempt to determine what sort of physical problem is causing his lack of mobility.
"He's having some trouble getting his arm in a certain position," said head athletic trainer Barry Weinberg.
"We want to see if there's something that's causing the mechanical breakdown -- if there's a physical issue causing a mechanical breakdown."
The news was much better for Pujols, who had been out with a strained right oblique muscle. After two days of intense workouts for Pujols, the club's medical staff consented to allow him to play. Pujols and manager Tony La Russa had hoped the slugger might actually play earlier in the week, while head athletic trainer Barry Weinberg had hoped to wait one more day.
"I just came up and talked to Barry and talked to Tony, and I'm playing," Pujols said. "That's it. If I feel something that is not normal, then I won't be out there."
When the Cards came to the park on Thursday, they hoped to be able to add Pujols to the roster, and they knew they needed to clear a spot for Reyes. Duncan was a natural choice to give up his spot to Pujols, but sidelining Mulder was not a certainty until Thursday afternoon.
"He had a setback, but it wasn't because he didn't know what he was trying to do," La Russa said. "He just couldn't get there. So what we were going to do was, we were going to throw a bullpen today just to see if he could get there. And we canceled the bullpen because even in the training room he couldn't get his arm up in that position."
Right-hander Sidney Ponson will take Mulder's scheduled start on Sunday. Ponson and Reyes are both expected to remain in the rotation while Mulder is out. Ponson, in a funk himself, had been moved to the bullpen before Mulder went down.
"I have to work on [everything]," Ponson said after throwing a side session. "I'm not throwing the ball pretty good the last couple times I went out there. So I worked on it, changed my mechanics a little bit, went back to my old mechanics. Hopefully that will work."
It's unclear how long Mulder will be out, but La Russa acknowledged that it might make sense to hold him until after the All-Star break -- pending the results of Paletta's examination, of course.
Edmonds scratched: A day after sustaining what the Cardinals called a "slight concussion," Jim Edmonds was a late scratch from the starting lineup on Thursday night. Edmonds was tentatively cleared in the afternoon, but after pregame warmups, he was removed from the starting nine.
"I feel a little different, but I'm all right," Edmonds said before the game. "I haven't really thought about it too much. I've been OK so far today. I'll just see how it goes."
Minor moves: Left-hander Jaime Garcia, who has emerged as a prospect to watch this year, was promoted from low Class A Quad Cities to high Class A Palm Beach. The move follows the end of the season's first half for both clubs. Garcia, 19, went 5-4 with a 2.90 ERA, 80 strikeouts, 18 walks, and just one homer allowed in 77 2/3 innings for QC.
Meanwhile, the Swing will also add an intriguing player, as fifth-round draft pick Shane Robinson will report directly to full-season ball. Robinson, a speedy outfielder out of Florida State, is skipping short-season baseball and going straight to Quad Cities. He was set to debut on Thursday night.
This date in Cardinals history: June 22, 2002, remains a date that will never be forgotten in the Cardinals organization. It's the day that rotation anchor Darryl Kile, widely regarded not only as a fine pitcher but an exemplary teammate, passed away in his Chicago hotel room. The Cardinals' game that Saturday was postponed after Kile's passing was discovered.
Baby birds: Triple-A Memphis got a huge game from Derek Wathan on Wednesday night, capped off by a 10th-inning walk-off home run. The Redbirds beat Albuquerque, 3-2. ... Double-A Springfield was off on Wednesday. ... Blake Hawksworth turned in another strong game for Class A Palm Beach, striking out 10 over seven innings in a 10-3 win over Daytona. Hawksworth allowed two runs on seven hits and did not walk a batter. Amaury Marti had three hits and Joe Mather homered and drove in four runs. ... Class A Quad Cities had an off-day. ... Short-season New Jersey picked up its first win, beating Williamsport, 5-2. Mark Hamilton went 2-for-4 with two RBIs, Rhett Parrott pitched three effective innings in an injury rehab start, and Tyler Norrick was dominating over four innings in his pro debut (one run, four hits, nine strikeouts, no walks). ... Thomas Pham began his pro career with a four-hit game, but rookie-level Johnson City lost, 11-7, to Bristol.
Wathan is the player of the day thanks to three extra-base hits, including the game-ender. He doubled twice to go with his homer, driving in two. He was acquired in trade from the Rangers organization earlier this month.
Coming up: Chris Carpenter receives a tough assignment on Friday night. Carpenter takes the mound against the team with the best record in the American League, the surprising Tigers, at Comerica Park. He'll be opposed by Justin Verlander with first pitch set for 6:05 p.m. CT.