It's a tough break for Gennett, who was hitting .258 with four home runs and a .361 on-base percentage.
"He was off to a good start, certainly, but hopefully [the injury] is minor," Counsell said.
Gennett felt tightness is his oblique in batting practice Tuesday and was scratched about 30 minutes before first pitch. He joins right-handed pitcher Corey Knebel (left oblique strain) and right-hander Matt Garza (right lat strain) on the DL.
"It seems to be a more common injury in baseball the last couple of years, but I don't have any explanation for it," Counsell said.
Counsell and the Brewers learned last year how careful teams have to be when players are coming back from these abdominal injuries. Right-handed starter Wily Peralta went on the DL with a left oblique strain last May, but the injury lingered and eventually caused him to be shut down for the season in September.
"You've got to be cautious, for sure," Counsell said. "It's involved in every movement you make in baseball."
Counsell said Gennett will be out for two weeks minimum before the team reevaluates him. In the meantime, Yadiel Rivera, Colin Walsh and Perez could all play at second base.
• Garza was moved from the 15-day DL to the 60-day DL on Thursday as he recovers from his lat strain. Counsell said this was an expected move to give Garza more time to prepare for starting Major League games.
"It's not a setback, it's just a timing issue," Counsell said.
• Counsell said Thursday the Brewers will not have any changes in their rotation after Wednesday's rainout. Taylor Jungmann started Thursday, and the rest of the rotation will stay in line.
• The Milwaukee Brewers and the Milwaukee Braves Historical Association will induct former Braves outfielder Bill Bruton into the Braves Honor Roll. There will be an induction ceremony at Miller Park on May 16 at noon CT.
Bruton played 12 seasons in the Major Leagues and was with the Milwaukee Braves from 1953-60. He hit .276 with 48 home runs, 327 RBIs and 143 stolen bases with the Braves.
Cody Stavenhagen is a reporter for MLB.com based in Chicago.