It's no great secret that the Ottawa Senators are a better team with Daniel Alfredsson and Jason Spezza in their lineup.

So now that both are back from injuries it's not surprising the Senators are on a roll.

Alfredsson played his fifth game Saturday since missing 11 with a shoulder injury and Spezza came back from a 20-game absence with a knee injury. Both scored in a 2-1 win over the Bruins that gave the Senators their sixth straight victory.

"I think we obviously got some key players back and our system is being executed very well," goalie Brian Elliott said after stopping 32 shots. "I think teams are having trouble with that."

Alfredsson, who had a hat trick in a 5-1 win at Boston Monday, scored in the first period and Spezza broke a 1-1 tie with 3:21 left in the second.

"I knew the guys were playing well, we went through a real tough stretch and we kind of got things together a bit so I wanted to play well," said Spezza, who has scored a goal in his last three games and six on the year.

The Sens, in the fifth spot in the Eastern Conference, have allowed seven goals during their winning streak.

"Everyone is contributing," said Alfredsson, who has five goals and nine points in his five games back.

The defeat was the fourth in a row and seventh in the last eight games for Boston, which has lost four straight for the first time since December 2007. The Bruins, in danger of slipping out of the top eight in the Eastern Conference, have lost five in a row at home, the first time the club has dropped five straight regulation home decisions since 2000.

"I'm not going to make excuses here, (we) gotta play better," Bruins coach Claude Julien said. "Everybody. (We) have to be better as a team. You play with emotion, you play with attitude, you play with a lot of things and you gotta find that if you want to really turn the corner."

Julien doesn't fault the team leaders for the slump.

"Let's not pick on leadership here because there's enough going on with our team that you don't start to pick on individuals," he said. "We have to play better as a team, that's what has to happen."

The Bruins, undermanned because of a string of injuries that has five regulars out of the lineup, have scored seven goals during the four-game losing streak, 15 in the last eight games. They had won the first four games of the season series with Ottawa before losing twice in six days.

The Bruins, who were booed by their fans at the end of the game, outshot Ottawa, 13-2, in the third period but never really had Elliott on the ropes.

Daniel Paille scored for Boston, in a game that saw both teams lose a goal to video review.

Boston's Tim Thomas made 13 saves in the first period, seven of them coming on a power play that also included Alex Kovalev hitting a post.

It appeared the first period would end scoreless, but Ottawa's Matt Carkner stopped Mark Recchi's clear at centre ice and that led to Alfredsson picking up the puck, going around Zdeno Chara and squeezing a wrist shot between Thomas' pads with 5.9 seconds left for his 14th goal of the season.

The Bruins tied it when Patrice Bergeron took a heavy hit at centre ice and got the puck to Paille, who walked down the left side and connected on a 35-foot slap shot high on Elliott's glove. It was his third goal in the last five games after going nine without one.

Ottawa then took the 2-1 lead when Kovalev carried the puck into the Boston zone and hit Spezza with a long pass. Spezza, who had scored a goal in each of his last three games, ripped a long wrist over Thomas' stick side.

Recchi kicked in the Bruins' disallowed goal, while Mike Fisher deflected an Alfredsson shot past Tim Thomas with a high stick for the two cancelled goals, both in the second period.