Center fielder Colby Rasmus, in the throes of a two-for-24 slump, said he won’t be able to play for the St. Louis Cardinals tonight. Rasmus has been advised to sit out because he spent part of the day today under general anesthesia as doctors used a procedure to try to determine the cause of Rasmus’ recent stomach discomfort.

Rasmus said he was told he had a hiatal hernia and gastritis although he said he won’t need surgery. “They said that I’m eating too much late at night, so it’s sitting on my stomach during the day. Then  I can’t eat right in the morning,” he said. “They said  it’s not real serious, but it cause irritation.”

Late-night meals are almost unavoidable for a ball player but Rasmus, 22, said, “It’s not working with my body, so I’ve got to change it up. I’ve just to change the way I eat and keep taking my medicine.  They said don’t eat anything late at night.”

Rasmus, who did not go out for calistenics or batting practice tonight at Busch Stadium, said he had been feeling weak lately but refused to offer that up as an excuse for his skid after he had played well for most of June.

“I’m not going to blame it on that,” said Rasmus, who added that he expected to be able to play on Tuesday night, although with 300-game-winning lefthander Randy Johnson pitching for San Francisco, Rasmus might not be in the lineup anyway.

Catcher Yadier Molina was out again with some stiffness below his right hip, the result of his having been slid into by Minnesota baserunner Michael Cuddyer on Saturday. He, too, said he expected to able to play on Tuesday. Molina was held out Sunday because he was unable to squat, manager Tony La Russa said.