"The temperature topped 90 even as the sun set behind Wrigley Field. Oppressive humidity smothered the ballpark. Every movement was a chore.

But this was Roy Halladay, baseball's equivalent of a marathon runner, trained for the long haul and programmed to chew up innings without anything more than routine maintenance.

So when Halladay stepped off the mound, bent over and placed his hands on his knees, sucking down deep gulps of heavy air, it was obvious something was wrong.

True to form, the Phillies' right-hander offered few complaints.

Sweat poured from his forehead, and he simply removed his T-shirt between innings to combat the heat.

He admitted to dizzy spells between innings, but Halladay told his pitching coach he wanted to stay in the game.

Staring in from the mound, Halladay could no longer make out the signs from his catcher -- and that's when he had enough.

Just five pitches into the fourth inning, Halladay made the long, slow walk back to the dugout, the shortest outing of his Phillies career.

Without their ace, the Phillies appeared as stagnant as the muggy July air, and the hapless Cubs, owners of the second worst record in the National League, slugged their way to a 6-1 win.

The story, of course, was Halladay.

"I've seen him get hot before," Charlie Manuel said, "but he was having trouble breathing too."

A 31-pitch third inning tested Halladay's will.

Seven batters came to the plate, four Cubs reached base, and two runners came around to score. After virtually every at-bat, Halladay bent at the waste, hoping to catch his breath.

In between innings, trainers placed wet towels on Halladay face and head to keep him cool. When he emerged for the fourth, he'd removed his undershirt."