PHOENIX -- Ultimately, the Mets' 5-4 walk-off loss to the Diamondbacks Friday night hinged on the simplest of miscalculations.

Mets reliever Scott Atchison tried throwing a cutter low and away, but he instead missed over the plate against All-Star first baseman Paul Goldschmidt, Arizona's most dangerous hitter.

"He made me pay for a bad pitch,'' said Atchison, who gave up Goldschmidt's 27th homer.

What left the Mets reeling wasn't Atchison's miscue but those that came before it, when potential rallies were blunted on a pair of critical baserunning blunders.

Marlon Byrd was thrown out at the plate in the second inning going for an inside-the-park homer -- with none out. And Juan Lagares made the third out of the seventh inning when he tried to stretch a double into a triple with the Mets down two runs.

"I have to be 100 percent that I'm going to make it,'' Lagares said. "That's my fault right there, big mistake.''

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Justin Turner knocked in three runs on a night in which he was in the lineup only to spell starting shortstop Omar Quintanilla. His biggest RBI came in the eighth inning, when the Mets rallied to tie it after trailing 4-2. Notoriously combustible setup man Heath Bell allowed three straight singles to load the bases, and Turner and Wilmer Flores each delivered an RBI groundout to tie it.

But it wasn't enough to combat one timely swing by Goldschmidt, who ended the Mets' winning streak at three.

The baserunning miscues haunted the Mets in what became a close game. Manager Terry Collins refused to criticize third-base coach Tim Teufel, who sent Byrd in the second inning when his drive kicked off the centerfield fence toward leftfield.

"He had a real good chance of scoring,'' said Teufel, who had not yet viewed a replay.

Collins thought Lagares should have "understood the circumstance'' when he made his ill-fated decision to try for a triple in the seventh.

Said Lagares: "There's no excuse about it. That's my fault right there.''

Of course, there was plenty of blame to be shared.

Entering the fifth, Mets starter Jeremy Hefner had allowed two hits and enjoyed a 1-0 lead. But with two outs, the Diamondbacks hit three consecutive doubles.

Opposing starter Patrick Corbin lined a double off the base of the wall in centerfield and scored the tying run when Adam Eaton doubled to right. Martin Prado gave the Diamondbacks the lead when he doubled in front of the 413-foot sign in center.

"I had the outfielders running all over the place,'' Hefner said. "[I] just wasn't very good.''

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In the sixth, Turner knocked in his second run of the game, this time pulling an RBI single through the hole into leftfield. But in the bottom of the inning, Wil Nieves' two-run double gave Arizona a 4-2 lead.