Braun missed six games last week with the same injury, returning to the lineup as a starter Sunday in Los Angeles -- he pinch hit Saturday.
On Monday, he appeared to be in pain after swinging and missing in his final at-bat in the sixth. He walked gingerly back to the dugout after the strikeout and was replaced in the field by Gabe Kapler.
Braun, batting .300 with a team-best 31 home runs and 86 RBIs, said he was fine and called it a nagging injury before Tuesday's game. He is day to day.
Milwaukee second baseman Rickie Weeks was also held out of the lineup with a sprained left thumb. He did not play on Monday, either.
The Brewers lost 5-2.
Information from The Associated Press contributed to this report.