Boston, MA (SportsNetwork.com) - Allen Craig scored the deciding run in a bizarre bottom of the seventh inning, and Boston trimmed Washington 8-7 in the second edition of a three-game interleague set.
Mookie Betts drove in two runs while Dustin Pedroia homered for the Red Sox, who have won the first two in this series and six of eight to begin the season. Daniel Nava and Brock Holt added an RBI apiece in the victory.
"I thought offensively we did a solid job from start to finish," Red Sox manager John Farrell said.
Edward Mujica (1-1) fanned two over 1 1/3 scoreless relief innings, while Koji Uehara turned in a quiet ninth for his first save of the year.
Michael Taylor posted two hits and drove in three for the Nationals, who have dropped five of their last six. Ian Desmond knocked in a pair but committed a defensive gaffe that led to the game-winning score.
"It's the same recipe," Washington manager Matt Williams said. "If you put all the ingredients together the same way every time, then you're going to get the same meal."
Blake Treinen (0-1) was responsible for the winning, though unearned, run while recording five outs in relief.
Trailing 7-5 in their second-to-last at-bat, the Red Sox picked up three runs without a hit to take the lead for good. Hanley Ramirez reached on a Desmond error, while both Shane Victorino and pinch-hitter Craig were hit by Matt Thornton pitches to load the bases with one down.
Treinen followed by bobbling an easy grounder from Ryan Hanigan near the mound and threw wild to home, which allowed Ramirez and Victorino to score. Holt then grounded to Desmond, who elected to get the out at first, allowing Craig to score the go-ahead run.
Junichi Tazawa came on for Boston with one away in the eighth and stranded a runner on second, then Uehara's lone scare was a long Ryan Zimmerman fly to left which just veered to the left of the left-field foul pole.
In the second, Desmond doubled and after a walk to Danny Espinosa, was caught stealing third. Espinosa moved to second on the throw and scored when Taylor followed with a single.
Boston got two back in the home half as Mike Napoli and Holt both singled and came in on Betts' two-out double to left.
The Sox picked up two more in the third thanks to back-to-back RBI singles from Nava and Hanigan, then Pedroia reached the seats above the Green Monster with one away in the fourth for a 5-1 lead.
The Nats chased Boston starter Justin Masterson with a six-run fifth. Masterson hit Jayson Werth with one down, gave up a single to Bryce Harper and walked Zimmerman, then Clint Robinson's hit and a Wilson Ramos groundout brought in a run each.
Desmond followed with a two-run single, moved to third on Masterson's wild pick-off throw and scored along with Espinosa on a triple from Taylor off Alexi Ogando after Espinosa was hit by Masterson.
Nats hurler Stephen Strasburg exited after a one-out hit from Holt in the sixth, but Thornton worked out of Craig Stammen's mess by retiring David Ortiz on a grounder with two on.
Pedroia finished the evening 3-for-4 with a walk ... The Red Sox have scored at least four runs in seven of eight games this season ... Washington has committed nine errors in eight games ... Nationals third baseman Yunel Escobar ended up 2-for-5 and has hit safely in seven straight games ... During that stretch, he is 10-for-28 (.348) with two doubles, three walks and two runs scored ... Prior to the game, Ramos was honored by the Red Sox by receiving the Tony Conigliaro award.