ST. LOUIS -- Cardinals outfielder Lance Berkman received a cortisone shot in his strained right shoulder on Wednesday but remains confident that he will be back on the field by Friday.

Berkman first felt discomfort in the area on his final swing in Sunday's loss to Pittsburgh and was held out of Monday's series opener against the Astros. The slugger started on Tuesday but was removed from the game after two at-bats when he felt discomfort once again when he grounded out in the fourth inning.

Berkman had an MRI on his right shoulder on Wednesday to pinpoint the exact location of the issue.

"It feels good, it's sore right now because of the injection," Berkman said. "I think, hopefully, by Friday I will be ready to go."

Wednesday's injection was not the first of the season for Berkman, as the six-time All-Star had a cortisone shot in his right wrist on June 4. He did not take part in batting practice on Wednesday and said he will see how he feels on Thursday before deciding when to pick up a bat.

"You just want to get to a spot mentally where you don't feel like you're going to hurt yourself if you turn it loose," Berkman said. "Hopefully -- just like with the wrist -- got the shot, knocked that out, I haven't had a problem with it since. So I'm hoping for the same result."

The switch hitter leads the National League with 27 home runs and is hitting .286 with a team-high 69 RBIs, while slugging at a .595 clip.

Skip Schumaker started in right field on Wednesday against Houston while Jon Jay assumed Berkman's role as the No. 5 hitter in the batting order.

Berkman insisted the injury would not cost him more than a few games.

"This is not a long-term thing, not a DL thing, just a couple [of days] thing," Berkman said.