WILMINGTON, Mass. -- Boston Bruins general manager Peter Chiarelli said his new No. 1 goalie has something to prove, which was the driving force behind the team and Tuukka Rask settling on a one-year, $3.5 million contract instead of a long-term deal.

"I think -- and you'd have to ask Tuukka -- he wants to prove that he's the No. 1 goalie for the Bruins for a long time," Chiarelli said in confirming the one-year deal Friday. "This was the easiest way to set the stage for that. Tuukka's been a really good goalie for us, but he hasn't been the No. 1 goalie (except for one year), and the stage is set for him, and we'll see where it takes us."

Rask was set to become a restricted free agent Sunday. The sides settling on a deal prevents other teams from being able to sign him to an offer sheet.

Rask, 25, will again be a restricted free agent after the 2012-13 season, meaning this one-year deal could result in a big, multiyear contract from the Bruins or, if he doesn't perform well, a much lower offer or no offer at all.

Chiarelli said the Bruins approached Rask about a multiyear extension, but the goalie insisted on the one-year contract.

"Again, it's a testament to Tuukka that he's willing to do it under the one-year contract," Chiarelli said. "He's a calm, poised goaltender -- you see a little bit of the fiery temper here and there, and I don't mind that -- but generally speaking he's a goalie who is composed. He's technically very good and athletic at the same time. I don't have any reason to think that he's not going to emerge as the No. 1 for years to come. We tried early on in the year to extend him out, and he took the same stance, which I respect."

With two-time Vezina Trophy winner Tim Thomas sitting the season out, Rask figures to be the Bruins' No. 1 goalie. He hasn't been the team's primary backstop since the 2009-10 season, when he allowed an NHL-best 1.97 goals per game.

Chiarelli, who said he never got the sense that teams would have come after Rask had he hit restricted free agency, acknowledged he was taking a risk. With the collective bargaining agreement expiring, there is at least a slim chance the new CBA will include provisions that would make Rask an unrestricted free agent after the 2012-13 season instead of an RFA.

"I saw some reports about that, and I think that's a risk that both sides were willing to take," Chiarelli said. "In an ideal world, this is a contract that we look to extend come January. If he is a UFA come next year, we'll just have to deal with it proactively, but that really didn't come into play."