WASHINGTON (WFAN/AP) — During a week when they had a chance to move into sole possession first place in the National League East, the Mets’ defense has let them down.

Second baseman Daniel Murphy committed two errors, one that contributed to three Washington runs, and the Mets mustered just three hits in a 5-3 loss to the Nationals on Wednesday night.

The loss was on the heels of Tuesday night’s should’ve-been game, which came unglued by gaffes in the field.

“You don’t have to look any further than this locker for where to start with some of our poor play the last couple of days,” said Murphy. “It starts right here. Got to get better, starting with me.”

Lucas Duda drove in a run and walked twice for New York. David Wright, Ike Davis and Kirk Nieuwenhuis had the Mets’ only hits against Washington starter Edwin Jackson.

New York has lost three straight and is now fourth in the NL East. The Mets committed three errors in a 12-inning loss Tuesday.

We haven’t played well defensively in the last three games, there’s no question, but for the most part we’ve played pretty good defense all year until now,” said New York manager Terry Collins.

Jeremy Hefner (1-3) allowed four runs, three earned, and seven hits over six innings. Three of those runs came on Adam LaRoche’s homer in the first inning.

Bryce Harper reached on an error by Murphy and Ryan Zimmerman walked before LaRoche hit a drive into the right-field bullpen.

“I wish I could have that pitch back,” Hefner said. “It hung for him practically on a tee.”

Murphy said Hefner never should have had to face LaRoche with two men on.

“I make that play on Harper and he gets to go after Zimmerman with nobody on,” Murphy said. “He’s got to be a little fine with the base open, and LaRoche made him pay, but he never should have been in that position to begin with.”

“It’s frustrating,” said Murphy, in his first season as the starter at second base.

“The learning curve is still there. It’s not something I’m happy about.”

Do you think the infield will plague New York all season long? Be heard in the comments below…

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