Bruins 3, Senators 1 .

BOSTON - Tim Thomas looked at a yellow piece of paper with his updated save percentage scribbled on it and broke into a smile, knowing he can now set a National Hockey League save percentage record.

"That's great. Awesome," he said after making 31 saves in Boston's 3-1 win over Ottawa on Saturday afternoon. "To be completely honest, I had a hard time getting it completely out of my mind the last couple of days."

Thomas increased his save percentage to .938, surpassing Dominik Hasek's league mark of .937 set in 1998-89. If he doesn't play the regular season finale Sunday — right now, Boston coach Claude Julien is leaning toward backup Tuukka Rask — the record is his.

Nathan Horton scored a tie-breaking goal early in the second period and the Bruins posted their seventh win in 10 games, leaving them in contention for the Eastern Conference's second seed with Pittsburgh and Philadelphia. Boston would have to win Sunday in New Jersey to have any chance, but also needs some help.

The Senators missed the playoffs for the second time in three seasons.

Daniel Paille and Rich Peverley had Boston's other goals and the Bruins completed the season series 5-1 against Ottawa.

Bobby Butler scored for the Senators and Curtis McElhinney had 26 saves. Butler, a rookie forward, finished the season with 10 goals, including markers in Ottawa's last three games of the year.

Senators head coach Cory Clouston told his team that he was glad they didn't let down during a tough season.

"I told the guys I'm really proud of how they played the last 27 games," he said. "I'm really proud of them."

The Senators won 15 of their last 27 games.

"For me, it was just a matter of taking the success we had the last 25 games. We have to build on that," said starting goaltender Craig Anderson, who had the day off. "Obviously, its not good missing the playoffs."

Six seconds after Ryan Shannon was given a double minor for high-sticking defenceman Adam McQuaid, Horton collected the rebound of Zdeno Chara's shot from the point, spun and slid a backhander into the net to move Boston ahead 1:08 into the second period.

Peverley made it 3-1 with a backhander in the slot with 5:08 left in the game.

The Bruins had jumped in front 1-0 when Paille redirected Gregory Campbell's pass from the edge of the crease 12:53 into the game. Campbell quickly collected a rebound of Shawn Thornton's shot at the side of the net and delivered a perfect feed in front.

The Senators tied it late in the first period when Butler scored off the rebound of his own shot when Thomas collided with a pair of players in front and ended up leaving the net wide open.

NOTES: Boston RW Mark Recchi played his 1,652nd game, passing Chris Chelios for fourth on the career list. ... The Bruins snapped an 0 for 12 power-play drought with Horton's goal ... Julien said after the game that Recchi and Chara will not make the trip to New Jersey ... Jason Spezza (21) finished as the only Senators player with 20 or more goals this season ... Ottawa went 2-26-2 this season when trailing after two periods. ... Julien bought six tickets and treated a family that had lost their home in a fire in late December.