"We can't make any excuses," catcher Carlos Ruiz said. "It was embarrassing."
Still, Ruiz sees hope.
"It's frustrating right now," he said, "but if we stay strong, a lot of good things can happen."
Starting pitcher Roberto Hernandez allowed five runs (four earned) in 51/3 innings.
"Hernandez had good stuff," manager Ryne Sandberg said. "It was a lack of run support and also a lack of sound fundamental baseball, basically."
The lack of fundamentals plagued the Phillies during this homestand, as it has throughout the season.
"You are going to make mistakes - it is part of the game," said second baseman Chase Utley, who had a costly error. "The thing we should try to do is learn from those mistakes and try to improve on them."
The Mets opened the scoring in the second on back-to-back doubles by Bobby Abreu and Lucas Duda.
Abreu, who was a late spring-training cut by the Phillies over concerns about his defense, went 5 for 13 with four runs scored and three RBIs in this series.
Matt den Dekker robbed Ryan Howard of a solo home run in the second inning, leaping high above the center-field fence to make an outstanding grab.
Den Dekker then saved another run by easily gunning down Reid Brignac at the plate after a single by Ben Revere in the third inning.
The Phillies wish that den Dekker had departed to Sin City.
Den Dekker was optioned to triple-A Las Vegas on Sunday but he stayed in Philadelphia, pending an MRI exam on centerfielder Juan Lagares. On Monday, the Mets placed Lagares on the disabled list with a strained muscle in his right side.
The Mets added four runs in the sixth inning. David Wright's two-run double to deep center field made it 3-0.
"That was a 2-0 pitch and I left it up to him," Hernandez said.
Wilmer Flores later added a two-run double off Mario Hollands.
The Phillies made it 5-1 on Ryan Howard's sixth-inning RBI groundout, his 40th RBI of the season and 15th in the last eight games.
Revere scored on a wild pitch in the eighth, but the Mets busted it open with six runs in the ninth on Curtis Granderson's two-run single off Jake Diekman and Flores' grand slam against Phillippe Aumont.
Maybe the best thing for the Phillies is hitting the road for three games in Washington and then three in Cincinnati.
"We didn't play that well this homestand, it's pretty obvious," Utley said. "There is nothing we can do about that now. We will try to improve, go on the road and try to win some games."