It was the first of Murphy's errors that proved most costly, coming on a Bryce Harper ground ball in the first inning that forced the second baseman to range to his left. Murphy arrived at the ball in plenty of time to field it and throw out the speedy Harper, but instead he kicked it toward the foul line, allowing Harper to race around to second base.
That made Hefner pitch carefully to Ryan Zimmerman, ultimately walking him. Which in turn gave LaRoche an opportunity to launch his three-run homer into the left-field seats, saying afterward that "he was looking for something to hit hard."
"It hung for him, right there on a tee," Hefner said. "He did what he's supposed to do on that pitch."
"LaRoche made him pay, unfortunately," Murphy said. "But he never should have been in that situation to begin with."
Murphy's second error was less flagrant, on a LaRoche grounder in the third inning that kicked up on him at the last moment. It was also less damaging, with Hefner inducing a double play one batter later to escape the ensuing jam. But it did serve to underscore the fact that Murphy, who has played so well in his first full big league season at second base, is hardly a finished product on defense.
"It's frustrating," Murphy said. "The learning curve is still there. It's not something I'm happy about."
On this night, it might not have been so exasperating had the Mets done any significant damage against Jackson, who walked four batters in seven innings but allowed just three hits. Though the Mets chipped away on Kirk Nieuwenhuis' RBI single in the third inning and run-scoring groundouts by Lucas Duda and Omar Quintanilla in the fourth and seventh, respectively, they could not push across the tying run against Jackson, nor against Washington's end-game duo of Sean Burnett and Tyler Clippard.
Instead, they watched the Nationals score a key insurance run in the seventh inning, after Steve Lombardozzi drew a leadoff walk against reliever Tim Byrdak, moved to second on Harper's single and tagged to third base on Zimmerman's pop fly. Though manager Terry Collins was frustrated that Byrdak did not appeal to second base on the play, replays showed that Lombardozzi did not leave the bag early. And he certainly did not leave early one batter later, when LaRoche plated him with a sacrifice fly.
Still, that rally was a minor hiccup compared to New York's defensive woes. The Mets lost Tuesday's game in large part because Jordany Valdespin made two late blunders at shortstop, and they have now committed eight errors over their last four games.
"We haven't played very well defensively, there's no question," Collins said. "I'm not going to say we are. But for the most part, we've played pretty good defense all year until now."
That defensive reputation began with Murphy, a natural third baseman who held his own at second over the first two months of the season. One of the club's most significant question marks heading into Spring Training, Murphy's defense had since become a stabilizing factor for the Mets.
So had his offense, which has also deteriorated in recent games -- in Collins' mind, the result of excessive tinkering with his swing. With Wednesday's 0-for-4 in his pocket, Murphy is now 0-for-17 dating back to June 3, dropping his OPS to .703. Murphy never endured such a cold streak last summer, when he was the league's fifth-leading hitter at the time of his season-ending knee injury.
"Dan knows hitting," Collins said. "But those guys that know hitting tinker, and we've got to get him back on track."
Murphy knows it. The Mets know it, too. His value to the team is significant enough that the Mets may not be able to win consistently without him producing.
"You don't have to look any further than this locker right here ... with some of our poor play the last couple days," Murphy said. "It starts right here. We've got to get better, starting with me."