"All the other innings, he's done a pretty good job," Cubs manager Dale Sveum said. "He's having trouble with those last three outs."
After Matt Garza pitched seven strong innings, continuously working out of trouble to keep the Mets from getting any timely hits, Marmol gave up a three-run walk-off home run to outfielder Kirk Nieuwenhuis to give the Mets a 4-3 win in front of 30,256 fans at Citi Field.
Marmol entered the game for the bottom of the ninth with a three-run lead. Sveum said it gave Marmol -- who's known to be erratic with now 21 walks this season -- some leeway in case he walked a couple batters.
It turned out that leeway wasn't enough.
Marmol surrendered a long home run to Mets outfielder Marlon Byrd to start the bottom of the ninth inning, and then walked Lucas Duda and gave up a single to John Buck.
"When Marlon hit the home run, it was a huge bolt of energy going through the bench," Mets manager Terry Collins said. "When Lucas walked, there were guys saying we were going to win."
Two batters later, they did.
Nieuwenhuis, who carried a .103 average into the game, hit a three-run home run of the facing of the second deck in right field to snap the Mets' three-game losing streak.
"You blow the save and lose the game. It's tough," said Marmol, who's now given up six home runs in 26 2/3 innings. "I left the pitch up, and it was right down the middle."
The loss also spoiled a solid performance by Garza.
He's had an inconsistent season, showing flashes of effectiveness interspersed among woeful outings. On Sunday, he looked vulnerable at times but made the pitches he needed to work out of trouble over seven innings, limiting the Mets to three hits with five strikeouts and two walks. He was in line for the win until Marmol gave it away.
"I felt pretty good about it," Garza said of his performance. "My location wasn't really there all the time. But I found a way to get through some jams. I just felt comfortable, and I felt like I had a little bit of a rhythm."
The Cubs' lineup couldn't get much going off Mets starter Jeremy Hefner. Chicago scored its first run in the first inning on an RBI single from Alfonso Soriano. Then the Cubs scored two more runs on a play that showed just how much the Mets were struggling.
With two outs in the top of the fifth, Starlin Castro singled and Nate Schierholtz walked. Soriano then hit a grounder to third baseman David Wright, who threw way wide of first base, which allowed Castro to score on the errant throw.
Then Mets first baseman Daniel Murphy retrieved the ball, and threw home. But like Wright's, his throw was way off and flew past catcher John Buck to the backstop. That allowed Schierholtz to score, giving the Cubs a 3-0 lead.
With the way Garza was pitching, it looked like that lead would be enough.
The Mets had runners at first and second with two outs in the fifth, but couldn't drive them in. They had runners at first and second with no outs in the sixth, and again, couldn't get the big hit.
Everything was in line for a win and sweep for the Cubs, until the bottom of the ninth.
"Just another strong outing from our starter is wasted again," Sveum said. "Garza was really good."
Sveum said he didn't want to use his normal closer, Kevin Gregg, for the ninth inning because he had already pitched four games in a row. Sveum wouldn't push it to five.
No one else in the bullpen has much experience closing. Sveum said he didn't want to use Shawn Camp, since he was just activated from the 15-day disabled list on Saturday.
So Sveum went to Marmol, who has 117 career saves, to get the last three outs. But Marmol couldn't nail down the win for the Cubs.
It came down to those final three outs.
"We all know that he's gotten a lot of saves in his career," Sveum said. "Still something's going on in the other innings that's not going on in that last inning."