For the second straight night, their inability capitalize on opportunities cost them in a one-run game.
''We got off to a good start,'' New York manager Terry Collins said. ''We just haven't been able to add on. We've had opportunities to put games away.''
The Mets twice left the bases loaded - letting a three-run lead slip away in the process - in losing 5-4 to the Cubs on Wednesday night in a mistake-filled game that featured a combined 13 pitchers.
Lucas Duda had a two-run double to lead a Mets offense that again failed to get the clutch hit. New York left the bases loaded in the fifth and sixth innings without scoring.
''As any hitting coach will tell you, in that situation the pressure's on the pitcher,'' said Collins, whose team also failed to score with bases loaded with none out during a 2-1 loss Tuesday. ''He's the one who's got the bases full. He's the one who's got to make pitches. All you've got to do is have some patience at the plate. . We've got to do a better job with that.''
The Mets have dropped two straight after winning three in a row and are 8-18 in one-run games.
Cubs starter Edwin Jackson (4-5) was victimized by his defense and his own lack of command, but managed to get through five innings, giving up five hits and five walks. Just one of the four runs he surrendered was earned.
''It's one of those things as starters we have to battle through,'' Jackson said. Nobody ever said things were going to go perfect in games you throw.''
Hector Rondon pitched the ninth for his seventh save in eight chances.
Mets starter Daisuke Matsuzaka didn't make it through the fifth, allowing four runs on four hits and five walks in 4 1-3 innings. Reliever Dana Eveland (0-1) gave up a run in 2-3 of an inning to take the loss.
The Mets scored three unearned runs in the first inning thanks to an error by Castro. With two on and two out, Bobby Abreu hit a sharp grounder up the middle. Castro booted the ball to allow a run to score.
Duda then compounded the Cubs' woes by doubling to left field to drive in two runs for a 3-0 lead.
The Cubs answered in the bottom of the inning with a pair of runs. Castro plated the first with a run-scoring single and the next batter, Nate Schierholtz, drove in the other with a groundout to first.
''I just wanted to try and pick up my teammates,'' Castro said. ''I tried to be aggressive at the plate and get those runs back for (Jackson).''
The Mets stretched the lead to 4-2 in the fourth when Ruben Tejada drilled a 2-0 pitch from Jackson for a solo homer. The Mets had a chance to tack on runs in the fifth after loading the bases with two out, but Anthony Recker popped out to first base.
The Cubs then pushed across three runs in the bottom of the inning for a 5-4 lead. With one out, Emilio Bonifacio singled and Justin Ruggiano walked. That was all for Matsuzaka as left-hander Eveland came on to face Rizzo, who promptly singled to load the bases. Castro followed with a single to center to drive in two runs and tie the score.
One out later, Chris Coghlan walked to load the bases and right-hander Jeurys Familia came on to face Mike Olt. Familia retired Olt, but not before bouncing a slider for a wild pitch that allowed Rizzo to score the go-ahead run.
Collins said his team may be feeling the effects of an unusual five-game series in Philadelphia that featured three extra-inning games, including two that went 14 innings.
''They haven't let down,'' Collins said. ''I just think sometimes you go through playing all those innings in all those days the way we did. We've got to find some energy somewhere''
NOTES: Cubs manager Rick Renteria was ejected in the third inning by home plate umpire Todd Tichenor for arguing balls and strikes from the dugout. It was Renteria's fourth ejection of the season. ... OF Andrew Brown joined the Mets Wednesday and will be activated Thursday. The Mets designated RHP Buddy Carlyle for assignment to make room on the roster.