Berkman described his knee, which was wrapped, as "stiff, for sure." He is also still unable to bend it.
Berkman's MRI is scheduled for Monday, following what is certain to be an uncomfortable four-hour flight back to St. Louis overnight. Though the club is withholding speculation on just what is wrong with Berkman, the Cardinals wasted no time getting someone here to take his spot on the roster.
Matt Adams joined the Cardinals from Triple-A as Berkman was placed on the 15-day disabled list. The move comes exactly one week after Berkman came off the DL. That stint was the result of a left calf strain.
"I didn't sleep great," Berkman said. "It wasn't because of the pain. It's just when you get hurt like that, you start thinking about what is it and what does it mean?"
Berkman went down at the end of the second inning on Saturday, just as he caught a routine putout at first base. He sat on the infield grass for a short time before needing help moving to the dugout. After the game, Berkman said he felt his knee buckle twice -- once initially and the second time when he tried to walk on his own.
There was, Berkman said, no discernible pop.
Berkman has dealt with knee injuries for years. He's had four surgeries -- two on each knee -- during his career. One of those procedures was to repair the anterior cruciate ligament in his right knee after the 2004 season.
Signed to a $12 million, one-year contract, Berkman has been limited to 42 at-bats this season because of injuries.
"We hope for the best with the [MRI] results that we get," Cardinals manager Mike Matheny said, "and keep swinging."