Braden Holtby made 32 saves for his eighth shutout of the season, Nicklas Backstrom became Washington's career assists leader, and the Capitals cooled the surging Boston Bruins with a 2-0 victory Sunday night.
Holtby rebounded from being pulled during the second period of Friday night's loss after allowing four goals on 22 shots.
Washington moved two points ahead of Boston for the first Eastern Conference wild-card spot.
Backstrom assisted on goals by John Carlson and Nate Schmidt, moving past Michal Pivonka and Alex Ovechkin (418 each) on the Capitals's assists list with 420.
The Bruins had won five straight, and were 7-0-1 in their last eight. Tuukka Rask, playing his second game in as many nights, stopped 36 shots.