Big Mac hits No. 19 as Cards rout Marlins.(Knight Ridder Newspapers)

ST. LOUIS _ Before Tuesday's game, someone asked John Boles what he thought about facing St. Louis' potent lineup.

"What are you trying to do, make me break out in a rash?" the Marlins manager said.

Get out the ointment.

The Marlins threw their best pitcher, Ryan Dempster, and the Cardinals treated him like batting practice, belting three homers _ including Mark McGwire's major-league-leading 19th _ and piling up nine hits and eight runs in five innings. By the time it was over, the Cardinals had pounded Florida 10-3.

Before Tuesday, Dempster had given up 19 runs all season, hadn't lost a game since April 15 and had the fourth-lowest ERA in the National League (2.74). He now has a 3.61 ERA, and the Marlins have lost five in a row and seven of their past eight.

"I wish I was facing myself tonight," Dempster said. "I stunk. That's the bottom line. That's a team you can't make many mistakes against, and I made too many. They earned it. They hit some pitches. They have some strong guys. The hardest part about this is I've got to wait five days to get back out there again."

It doesn't get any easier for the Marlins, who face the Cardinals two more times before heading for Cincinnati. Florida pitchers have given up 53 hits and 39 runs in their past four games, with opponents hitting .338 in that stretch.