The announcement by general manager Ed Wade came two days after Berkman underwent an MRI on his calf at The Methodist Hospital in Houston. Dr. David Lintner reported that the MRI revealed a Grade 2 strain.
Berkman has been experiencing discomfort in his left calf since the Astros' July 16 game in Los Angeles, which he was forced to leave after straining it while running the bases. Since then, he had made just one start and two pinch-hit appearances.
"It's for the best," Berkman said. "I want to be on the field, so I'm not happy about it, but it's for the best. I look forward to getting it right and getting back on the field in a couple of weeks. It's better to be out a couple of weeks than a couple of months."
On Tuesday, the Astros said they thought he would only be out of the starting lineup for two or three days. But after speaking with doctors, they chose to place the five-time All-Star on the DL.
"I spoke with Dr. Lintner today, and we are in agreement that keeping Lance active will only put him in a position of wanting to help the club and reaggravating the injury," Wade said. "I also spoke to Lance, and he understands. It's not easy to disable one of your key guys, but we want him strong for the stretch drive, so it's the right move."
Berkman is hitting .273 with 18 home runs, 55 RBIs and 69 walks in 89 games this season. It will be just his second stint on the DL in his 10-plus seasons in the big leagues. The only other time he's spent time on the shelf with an injury was from March 30-May 6, 2005, while recovering from offseason surgery on his right knee.
Maysonet is scheduled to join the team Friday in Houston for his second stint with the Astros this season. The 27-year-old hit .315 in 19 games for the Astros during his first stint with Houston from May 22-June 27. He was hitting .241 in 45 games with one home run and eight RBIs at Round Rock.
Jason Grodsky is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.