BOSTON (AP) — Jack Eichel scored twice in his return to Boston, Jamie McGinn had the go-ahead goal with 5:36 left and the Buffalo Sabres rallied from a two-goal deficit in the third period for a 6-3 win over the Bruins on Saturday night.

Ryan O’Reilly also scored twice for the Sabres, who broke loose for five goals in the third to win for the fourth time in six games. Chad Johnson stopped 30 shots, and Evander Kane had the other Buffalo goal.

Matt Beleskey, Patrice Bergeron and David Krejci scored for Boston, which lost its second straight in regulation after going 11-1-3 in its previous 15 games. Backup goalie Jonas Gustavsson made 23 saves.

Eichel, the No. 2 pick in the NHL draft last summer, also had two assists. He grew up about 35 miles north of Boston and starred for one season at Boston University.

Eichel last played in TD Garden when BU lost the NCAA championship game to Providence last season. He won the Hobey Baker award as college hockey’s top player before entering the draft after his freshman year.

McGinn lifted a backhander over Gustavsson for the game-winner. Eichel’s empty-net goal was the first of two in the closing 2 minutes. O’Reilly added one seconds later.

Buffalo erased a two-goal deficit in 39 seconds midway into the third. O’Reilly scored from the left circle after collecting a puck that bounced off the back boards, cutting it to 3-2.

Eichel fired a shot that caromed into the net off Boston defenseman Kevan Miller, tying it with 9 minutes to play.

Trailing 1-0, the Bruins scored twice in a 76-second span. Beleskey tied it when he tipped Miller’s shot past Johnson at 5:49.

Boston moved ahead when Bergeron slipped a wrister between Johnson’s pads.

Krejci batted his own rebound out of the air just under 7 minutes into the third.

Buffalo had moved ahead when Kane scored off a rebound.

NOTES: Bruins GM Don Sweeney said the club could make F David Pastrnak available to the Czech Republic to play on its national team in the 2016 World Junior Championships when the NHL’s roster freeze ends on Dec. 28 if Boston doesn’t have any injuries. Pastrnak missed seven weeks with a broken left foot before playing two games in the AHL. Sweeney said he hopes the experience would help the 2014 first-round draft choice’s confidence. “That would be our hope, that he returns with that,” Sweeney said. The Sabres had been off since a 3-2 shootout loss against Chicago at home last Saturday. . Boston D Torey Krug left with an undisclosed injury. . Boston is at Ottawa on Sunday, the first of a home-and-home set. The Sabres next play Monday when they host Washington.