In 13 games, Rask (8-4-1) has a 1.61 goals-against average and .945 save percentage, both best in the NHL. He recently had a shutout streak of 170:26 and is riding a four-game winning streak with two shutouts during that stretch.
The situation presents Bruins general manager Peter Chiarelli with a problem any GM would love to have. Thomas, 37 and still at the top of his game (16-6-0, 1.94 GAA, .939 save percentage), is under contract through next season at a salary cap hit of $5 million. Rask, 24, is due to become a restricted free agent July 1; if he continues his stellar play, he rightfully could expect a decent raise from his $1.5 million salary. And who could blame Rask if he preferred to go elsewhere for a chance to be another team's No. 1?
Chiarelli wouldn't comment on negotiations but did say in an email that "Tuukka is a large part of our present and our future."
And that's just fine with Rask, whether he's the starter here or not.
Following practice Tuesday, Rask made it clear he wants to remain with the Bruins for the long haul.
"I think everyone does," Rask told ESPNBoston.com. "I bet a lot of guys want to come and play here as well. We've got a good group of guys here that have been here for a couple of years now and I think that's my goal as well.
"I haven't really put a lot of thought into it, but he's [Thomas] got a year left on his contract and mine is up obviously, but I want to stay here. I'm sure they have a plan for that too and it will all work out good. I'm a young guy and I want to have a long future ahead of me as a Bruin and make more good things happen for the team and our fans."
Rask was asked if he'd be willing to open contract talks now should Chiarelli approach him or his agent?
"Yeah, for sure. Offer me 10 years and a hundred million, I'll take it!" Rask joked.
That positive, easy-going approach is a big factor in Rask's success this season. Instead of letting a contract year serve as a distraction, Rask has used it as motivation.
"You don't want to think about it too much, but obviously it's a contract year and you want to prove something," Rask said. "You've got to find a job eventually and you try to have the best season possible and get a good contract."
Rask, who said he and his agent have not had any talks with Chiarelli, was the Bruins' starting goalie in 2009-10, when he went 22-12-5 with a 1.97 GAA and .931 save percentage. But early in the 2010-11 season, Thomas, coming off hip surgery, was otherworldly, moving ahead of Rask on the depth chart and leading the Bruins to their first Stanley Cup in 39 years in the process.
Rask struggled with the adjustment of his role at times last season, but he did his best to turn his difficult experience into a lesson. He has worked hard to not let the frustration of being a backup set in and feels it has helped him bounce back this season.
"Obviously I expected Tim to have most of the starts again, but I think last year helped me a lot to be mentally prepared and not take it too personally," Rask said. "Now I know how to be ready all the time and not just focus on that one game I play here and there.
"Last year I would put my focus on one game and if I played bad, it was the end of the world sometimes. Or I didn't stink and I still lost and then I didn't play for a week. That got to me for sure. But now I am more mentally tough, so that experience really helped me. Now I just don't let it get in my head and just keep playing my best."
James Murphy covers the Bruins for ESPNBoston.com.