BOSTON - Two errors by pitcher Blake Treinen allowed Boston to erase a seventh-inning deficit against Washington, and the Red Sox won 8-7 on Tuesday night as the Nationals struggled in the field for the second consecutive game.

Boston went ahead with three unearned runs without a hit in the inning, which included three errors.

Hanley Ramirez reached first base on a fielding error by shortstop Ian Desmond to start the rally. Shane Victorino was hit by a pitch from lefthander Matt Thornton. After Mike Napoli's flyout sent Ramirez to third, Treinen replaced Thornton and hit Allen Craig, loading the bases.

Treinen then fielded Ryan Hanigan's bouncer in front of the plate, dropped the ball as Ramirez scored, then threw it past catcher Wilson Ramos as Victorino came home with the tying run. Craig scored the go-ahead run on Brock Holt's groundout.

In Boston's 9-4 victory Monday, the Red Sox took an 8-0 lead in a four-run third when center fielder Michael A. Taylor allowed a ball to drop next to him on the warning track, Bryce Harper and Taylor had one fall between them in right center, and Desmond didn't handle Mookie Betts' grounder in the hole with the bases loaded.

Boston third baseman Pablo Sandoval left Tuesday's game in the sixth with a bruised left foot after being hit by a pitch in the bottom of the third. Dustin Pedroia hit his third homer this season.

Edward Mujica got the victory and Koji Uehara got his first save, one day after coming off the disabled list.

Washington reached Justin Masterson for six runs in the fifth as they sent 10 batters to the plate.

Desmond had a two-run double and Taylor a two-run triple in the inning, which started with the Nationals loading the bases on a single, hit batter and walk.