Pirates third baseman Pedro Alvarez delivered the big blow in the first inning, crushing a three-run homer to give the Bucs a 4-0 lead. The Mets rallied back with three runs in the bottom of the frame with back-to-back homers by Justin Turner and David Wright off Wandy Rodriguez -- the first back-to-back home runs for the Mets this season -- but Pittsburgh answered with three more off McHugh the next inning and added another run in the fifth when Elvin Ramirez walked Alvarez with the bases loaded.
"It comes down to execution," McHugh said. "I executed really well that first game, and I've executed really poorly the last couple outings."
An irregular workload and overall fatigue have seemingly caught up with the right-hander. Strictly a starter in the Minors, McHugh has made two relief appearances with the Mets, if for nothing else but to get him time on the mound. As for the innings, McHugh logged 148 1/3 in the Minors this season, and an additional 20 with the Mets, well exceeding his previous career high of 132 1/3 set in 2010.
"I truly believe he's running out of gas," manager Terry Collins said. "You accumulate all of the innings he has this year, pitching in September for the first time. His stuff is not as crisp as it was the first outing. His curveball, which is still a good pitch, is not as sharp as it was earlier."
The loss put a damper on a monumental night for Wright, who finished the evening 2-for-4 with three RBIs, tying Ed Kranepool's all-time franchise record of 1,418 hits. He also hit a sharp line drive to third base in his second at-bat, but Alvarez made a backhanded snare to record the out.
"You'd like to do these types of things in wins, but I'm proud of the fact that I was able to tie it and hopefully break it tomorrow," Wright said. "But it's bittersweet, especially playing behind that eight ball early in the game."
Tuesday marked Wright's 1,255th career game. Kranepool, who played for the Mets from 1962-79, took 1,853 games to reach that mark.
Wright's second hit -- a seventh-inning two-run single -- brought the Mets within two runs, but Pirates manager Clint Hurdle attempted to make a case that the inning should have ended before Wright's at-bat. Daniel Murphy hit a ground ball to third base, but Alvarez tagged an advancing Jordany Valdespin without the ball in his glove before making the throw to first. Hurdle came out to argue -- a double play would have ended the inning -- but Valdespin was ruled safe and ultimately scored on Wright's ensuing single.
Mets reliever Robert Carson left the game in the seventh inning with a left elbow strain, departing with one out and two strikes on Josh Harrison. X-rays came back negative, but he is scheduled to have a precautionary MRI on Wednesday.
A win would have made McHugh the fifth Mets pitcher this season to record his first Major League victory, a significant figure considering the components of next season's bullpen are anything but settled. Collins and company have stressed that young arms like Carson and McHugh -- regardless of their roles in the Minors -- will certainly be given consideration for relief roles come Spring Training.
"No matter what happens, on Oct. 4, next season starts for all of us," McHugh said. "We're going to go out and give it all we have for the next [seven] games, and then this offseason becomes super important for a lot of us."