Meche was bothered by back spasms early in spring training. He was also uncomfortable in an April 17 start at Texas.

"I can't make any predictions about his next start," Royals manager Trey Hillman said. "He was masking it pretty good. He had lower back stiffness that had been bothering him for the better part of the game. He wanted to stay out there and compete."

Meche allowed five runs, seven hits and five walks before assistant trainer Frank Kyte and Hillman came to the mound in the Blue Jays' four-run fourth with Adam Lind at the plate. Robinson Tejeda replaced Meche.

"Right now, I'm scheduled to pitch (Sunday), so we're going to try to readjust some things, see what we can come up with as far as switching exercises, stretching, maybe doing some things I haven't been doing," Meche said.

"I never had anything back-wise, ever, so it's kind of annoying. I don't think there is any kind of structural damage as far as tears or anything. It comes and goes. I'm not concerned."

Meche, the Royals' opening-day starter, is in the third year of a five-year, $55 million contract.

BLUE JAYS 8, ROYALS 1: Gil Meche left in the fourth with a stiff back, putting the Royals in a 5-0 hole. Jose Guillen, who hit two home runs Monday, popped up foul to the catcher on the first pitch to leave the bases loaded in the third. David DeJesus drove in the only Kansas City run with a fifth-inning double. Relievers Horacio Ramirez and Kyle Farnsworth gave up three runs on five hits in the eighth to put the game out of reach.