PHILADELPHIA — It’s a good thing the suddenly punchless Mets began the week with a double-digit lead in the National League East. Between their shoddy play in Philadelphia and the news that Pedro Martinez is beginning a stint on the 15-day disabled list, the Mets are suddenly in need of their cushion.

Jon Lieber pitched his first shutout in more than five years, Chris Coste hit a tworun homer, and the Philadelphia Phillies won their third straight over the Mets, 3–0 last night.

Seemingly out of the playoff picture on July 30 after trading Bobby Abreu as part of a roster overhaul, the Phillies began the day only 2 1/2 games behind Cincinnati in the NL wild-card race and showed some life against the best team in the league.

Philadelphia took the first three games of this four-game set with sharp pitching and big hits. The Phillies thumped the Mets by a combined 24–4 score in the first two games of the series.

Lieber (5–9) was terrific, putting together his third straight solid start since an awful outing against Florida on the day of the trade deadline. He scattered five hits, walked none and struck out four for his second complete game this season and first shutout since May 24, 2001, with the Chicago Cubs.

Lieber threw 72 of his 101 pitches for strikes last night in a game that took just 2 hours, 3 minutes.

Hours after the Mets put ace Pedro Martinez on the disabled list with a strained right calf, Tom Glavine (12–6) gave the sagging rotation and tired bullpen a boost with an effective seveninning stint.

After the Phillies scored a combined 10 runs in the first inning of the last two games, Glavine retired the side in order to start this one. The offensive damage was only delayed an inning.

Glavine hit Ryan Howard with a pitch to open the second and, three batters later, Coste hit his fifth homer into the second row of the left-field seats. Coste also doubled and singled.

Glavine allowed six hits, three runs, and lost his second straight start.

Martinez went only one inning in the first game of the series and Orlando Hernandez was roughed up for 11 runs in four innings on Tuesday. Martinez was placed on the 15-day disabled list yesterday with a minor strain in his right calf, a move manager Willie Randolph called a “precaution.”

“He felt he couldn’t get as loose as he wanted to,” Randolph said before last night’s game. “It wasn’t anything we talked about prior to the game. He said he had it for a couple of games. Sometimes it loosens up, sometimes it doesn’t. Any time you have to take him out over something like that, I think it’s important to take precautions and put him on the DL.”

In his second season with the Mets, Martinez is 9–5 with a 3.84 ERA in 20 starts. He missed a month earlier this season because of inflammation in his right hip. He has 125 strikeouts and 35 walks in 122 innings.

“I think the main thing is that his arm feels great,” Randolph said. “He’ll be able to do his long toss and keep his arm strong. I’m sure if we were in a different situation later in the season, I’m sure he could have gone out and pitched the way he has off and on the last couple of times out.”

Right-handed reliever Heath Bell was recalled from Triple-A Norfolk to take Martinez’s spot on the roster.