Manager Fredi Gonzalez said he made the decision because Coghlan was sore from a diving catch, not because he's hitting .132.
"He said, 'Well, I'm glad you took it out of my hands, because I'm pretty sore," Gonzalez said.
Last season's NL Rookie of the Year landed hard after making a spectacular grab on the warning track in the 11th inning of Tuesday night's loss to the Reds.
"When I dove in the outfield near the end, I felt something," Coghlan said, "Right under my ribs. It's nothing big, nothing serious."
Coghlan has only one hit in his past 23 at-bats but said he didn't need a mental break and hopes to be back in the lineup within a couple of days.
Brett Carroll replaced Coghlan in left field.