CHICAGO -- Carlos Marmol sat in the locker room putting on his shoes.
"What a day, huh?" Marmol said.
The Cubs closer, who had given up only three earned runs in 23 innings before Tuesday, allowed six runs in the ninth to give the Astros a 7-3 win.
Pinch-hitter Matt Downs hit a two-run double to tie the game, Michael Bourn hit the go-ahead RBI single, and Hunter Pence lined a three-run homer, all off Marmol.
"I can't remember the last time I gave up a home run," said Marmol, who was vying for his 11th save.
A refresher for Marmol: He last did so on May 15, 2010, to Pittsburgh's Jeff Clement.
The Cubs had taken a 3-1 lead in the eighth to put Carlos Zambrano, who threw eight innings of one-run ball, in line for his sixth win. After the Cubs tied the game on a throwing error by Houston starter Jordan Lyles, who was making his Major League debut, Darwin Barney hit a tiebreaking double that was followed by Aramis Ramirez's RBI double.
Brett Wallace started the ninth with a single off Marmol (1-2). Chris Johnson then doubled before the floodgates opened. After recording one out in seven batters and giving up five hits and a walk, Marmol was removed and booed as he walked off the field.
"It doesn't bother me because I deserve that," he said of the reaction. "I gave up the lead in the ninth, what can I say? I can't say anything."
Marmol hadn't allowed six runs in a game since Aug. 13, 2006, when he started against the Rockies. Tuesday was his first time allowing six runs as a reliever.
"This one will hurt a little more than others," Cubs manager Mike Quade said.
Until the eighth, the Cubs struggled against Lyles, who became the youngest player to make his Major League debut as a starting pitcher at Wrigley Field since Zambrano made his in 2001.
Zambrano struck out against Lyles in the fifth and responded by cracking his bat on his right thigh.
"I don't like that," Quade said. "I'm glad he's OK. I get his frustration, but do something else. I cringe because he's going to hurt himself."
Quade said he didn't share his thoughts with Zambrano.
"He knows [I don't like] that," said Quade, who turned away before Zambrano broke the bat. "I don't have to tell him that."
Zambrano made no apologies.
"This is not the first time [I've done] that," he said. "I know that I have to be careful, but if you guys want to know how I [broke] this bat, just come tomorrow and see me lifting weights."
What about his manager?
"He don't like it, he don't like it," Zambrano said. "What can I do?"
Lyles, 20, said it was entertaining.
"I heard it and then I looked and saw the rest of it," he said. "That's pretty cool. That's my first and probably going to be my only one. Guy's a great pitcher and a great athlete."
Quade was still pleased by the outing of Zambrano, who went eight innings for the third time this season.
"I'm concerned about his emotion at that moment, but I'm more concerned about him going out and getting outs, which he did, and he did all night," Quade said.
Zambrano said he went up to Marmol after the game and told him to keep his head up.
"He was like, 'You're not going to be perfect," Marmol said.
Alex Ruppenthal is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.