"I understand the situation," said Hamels, who will oppose two-time Cy Young Award winner Johan Santana. "It matters. (Pitching) every five days, that's what I've been able to do all year. I know I can do it (now)."

Said pitching coach Rich Dubee, "This kid has prepared himself all year, and he's preserved himself well. Right now, I think he's physically fit enough to do this. And being a big game against the Mets, I'm very confident he'll rise to the occasion."

Hamels, who has a checkered injury history, leads the National League with 203 innings, and the Phils could've given him an additional day of rest and started struggling right-hander Kyle Kendrick on his regular turn. But the gravity of the series against the Mets trumped handling Hamels with extra care.

"We're not overextending him," manager Charlie Manuel said. "It's his regular day."

It will mark only the second time this season that Hamels has faced the Mets and the first since a 6-4 loss April 18, also against Santana. It'll also be only the second time has made three straight starts on regular rest. He went 1-1 with a 1.99 ERA against the Braves, Cardinals and Diamondbacks from July 3-13.

But Hamels actually has pitched more effectively with normal rest (2.47 ERA in 16 starts) than extra rest (3.95 ERA in 12 starts). Hamels said his arm often is the sorest on the second day after a start. But, by the fourth day, he's ready once again to unleash 100 or so pitches.

"Mentally, your body is ready that fifth day," Hamels said. "When you get that extra day, sometimes you feel off.

"The main guy, when it's the playoffs or the championship or a big division rivalry, that's what I want to be, and that's what I've been able to learn. Finally, I get that time to step up to the plate. I definitely know I'm ready for it."

NATIONALS 9, PHILLIES 7: Ryan Howard hit two homers, raising his majors-leading total to 39, but the Phillies bullpen allowed five runs in the seventh and eighth innings of the rubber game of a three-game series in Washington. With a 5-4 lead, Chad Durbin served up a game-tying homer to Ryan Zimmerman in the seventh before combining with J.C. Romero to allow four runs in the eighth. Jimmy Rollins, Howard and Pat Burrell had two hits apiece for the Phillies, who dropped to three games behind the division-leading Mets, their largest deficit since May 11.