NEW YORK (WFAN/AP) — Dillon Gee’s impressive start seems a long way back.

Gee had his worst outing of the year on a night when Cliff Lee was excellent, and the Mets lost 10-0 to the Philadelphia Phillies on Monday.

John Mayberry Jr. and Hunter Pence each hit a two-run homer and the Phillies rocked Gee (11-5) to earn their major league-best 82nd win. They have a comfortable lead over Atlanta in pursuit of their fifth straight NL East title.

Lee (14-7) allowed three hits, walked three and struck out seven. The 2008 AL Cy Young Award winner is 4-0 with a 0.58 ERA this month.

Gee gave up eight runs and seven hits in 3 2-3 innings, increasing his ERA from 3.92 to 4.37. The rookie is 4-5 since a 7-0 start.

“It’s frustrating,” Gee said. “Nothing went my way. Probably the worst game of my life.”

Listen: Mets’ Gee after another rough outing

David Herndon pitched the last two innings to complete the five-hitter and record Philadelphia’s 17th shutout.

Lee, who gets standing ovations for almost anything he does in Philly, got yet another one after flying out to the left-field warning track in the seventh, just missing his third homer of the season.

The Mets have lost four in a row and 16 of 21.

“We’re not hitting and not pitching,” manager Terry Collins said. “That’s a bad combination.”

The Phillies scored their first eight runs with two outs. They got three on three straight two-out hits in the second. Pence led off the inning with a single and advanced to second on a wild pitch. He scored on Wilson Valdez’s RBI single down the first-base line. After Lee singled, Shane Victorino lined a two-run triple into the right-field corner.

Lee took an awkward stride around third and the Mets appealed that he missed the bag, but umpire Jim Reynolds called him safe. Replays showed Lee touched the inside corner of the base.

Mayberry connected to make it 5-0 in the third. He’s been on a tear since his latest recall from Triple-A Lehigh Valley on July 5. Mayberry, a fourth outfielder and pinch-hitter, is batting .318 (27 for 85) with eight homers and 26 RBIs in 30 games.

“I’ve obviously made changes with my stance and approach,” Mayberry said. “Additionally, it doesn’t hurt to get more at-bats.”

Mayberry walked with two outs and the bases loaded to force in another run in the fourth. Ryota Igarashi replaced Gee and allowed a two-run single to Carlos Ruiz that put the Phillies up 8-0.

“He tries to be too fine sometimes and he just didn’t have command of anything,” Collins said of Gee. “Our bullpen is so thin we tried to pitch him out of trouble and he didn’t do it.”

Pence took Igarashi deep in the sixth for his fifth homer since coming to Philadelphia in a trade with Houston on July 29.

The Phillies played without shortstop Jimmy Rollins. The 2007 NL MVP was placed on the disabled list with a strained groin. All-Star third baseman Placido Polanco was activated from the DL and went 2 for 4.

Mets shortstop Ruben Tejada made an outstanding, over-the-shoulder running catch on a foul pop by Chase Utley in the third. Phillies first baseman Ryan Howard made a similar catch on a foul pop by Scott Hairston in the fourth. Tejada ran into the tarp on his, while Howard slid before reaching the railing.

“I walked a few guys and hit a batter. Not happy about that,” Lee said. “But, they didn’t cross the plate.”

What’s wrong with Gee? Be heard in the comments below…

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