Morrison, who started in left field and went 1-for-3 in Wednesday night's inaugural game at Marlins Park, is still nursing a sore knee. The combination of a day game after a night game, and the relatively cool weather in Cincinnati, factored in the decision to keep Morrison on the bench.
Despite playing nine innings for the first time since last season, Morrison said he was encouraged by how good he felt after Wednesday's game.
"It actually feels pretty good today, probably better than it did yesterday," he said. "With the day off tomorrow ... it'll feel that much better on Saturday. It's day by day."
Marlins manager Ozzie Guillen said he planned to limit Morrison whenever possible as a precautionary measure.
"We had a plan," Guillen said. "He's not starting today, we have a day off tomorrow. Hopefully that'll give him more time to recover and prevent any problems. We don't want to babysit him. But we need to be careful."
Despite the quick departure for Cincinnati after Wednesday night's game, Morrison said there was ample time for him to get treatment on the knee following Miami's opening loss.
"We got all that stuff done," he said. "Unfortunately we didn't swing the bat well, so it was a quick game."