Castro legged out a run-scoring infield single in the 11th inning, and the Cubs blanked the punchless Mets 2-0 Wednesday night for their second consecutive shutout at Citi Field.
"We're a little bit challenged offensively right now," Chicago manager Joe Maddon said. "A lot of times teams will sink because of that. We have not and I really appreciate that a lot."
Jon Lester threw seven sharp innings and the Cubs overcame a major baserunning blunder to score twice in the 11th. Miguel Montero added an RBI single as Chicago won its eighth straight against the Mets, including the first six meetings this season.
"Obviously we left some guys on base, but in the end we ended up getting the hits and that's why it's a good win. Our pitching's been fantastic," Cubs outfielder Mike Baxter said.
The staggering Mets botched a suicide squeeze in the eighth and a double-play ball in the 11th during their latest flop at the plate.
New York was held under two runs for the 20th time this season, tied for most in the majors.
"It's tough. Essentially it's centered around me," said No. 3 hitter Lucas Duda, who went 0 for 5 with four strikeouts. "I'm not doing my job, not getting the job done, not driving runs in, not moving runners over."
Montero made it 2-0 with a single off Sean Gilmartin -- all that prevented the Mets from losing 1-0 in consecutive home games for the second time since early May.
Jason Motte (6-1) fanned two in a hitless inning and Justin Grimm threw a called third strike past Kevin Plawecki with runners at the corners for his first major league save, bringing a final round of boos from the crowd of 23,906.
"I just love when your team wins an extra-inning game on the road," Maddon said after his club improved to 9-4 in extra innings overall.
Lester and Bartolo Colon took advantage of the feeble lineups they were facing. Colon allowed only three hits in seven innings and retired 14 straight following a leadoff double in the third.
With his own team slumping at the plate, the colorful Maddon brought in an illusionist from Las Vegas to entertain his team before Tuesday night's game. Chicago won 1-0 to stop a five-game slide, and counterpart Terry Collins was asked Wednesday about Maddon's magic touch.
"I brought in a witch doctor to clean out the clubhouse, get all the bad spirits out of there," Collins said, drawing laughs. "We need to send a magician down to St. Lucie where all the rehab guys are."
Aside from mixing potions, Collins tried almost any trick he could think up in a desperate attempt to help the Mets push across a run.
He let Colon swing away with a runner on second and none out, then called for a suicide squeeze in the eighth with two men in scoring position.
"You have to start thinking outside the box, because inside the box isn't working," Collins said.
New York nearly had two runners tagged out on the play, but umpires kept Murphy at third base following a long huddle and discussion with Maddon.
"I think they saw it properly," Maddon said. "There was nothing for me to argue about. I was just, like, messing with them a little bit."
Ceciliani struck out against Pedro Strop to end the inning.
Colon had received a decision in 27 consecutive outings, going 16-11 since July 23, 2014. That was the longest such streak in club history and the longest in the majors since he went 30 games in a row from 2004-05 with the Angels. This was Colon's first no-decision in 24 home starts with the Mets.
Cubs: OF Jorge Soler (sprained left ankle) got a scheduled night off at Triple-A Iowa after going 0 for 7 in the first two games of his rehab assignment. ... 2B Addison Russell got some rest, something Maddon said he wants to do regularly with Russell and Bryant in the second half as the rookies adjust to the length of a 162-game major league season. Russell entered as a pinch hitter in the 10th and stayed in the game.
Mets: LF Michael Cuddyer sat out with a sore left knee and might not play Thursday afternoon, either, Collins said.
Cubs: RHP Jake Arrieta (7-5, 2.94 ERA) tries to pitch Chicago to a season sweep of the Mets on Thursday. He struck out a season-high 10 in eight innings of three-hit ball for a 6-1 victory over New York on May 12.
Mets: With All-Star selections set to be announced early next week, RHP Jacob deGrom (8-5, 2.15 ERA) looks to add to his impressive credentials.
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