ST. LOUIS -- Unrestricted free agent center Paul Stastny was one of the big fish on the open market Tuesday.

Stastny, 28, was the St. Louis Blues' top target and they landed the former Colorado Avalanche center, signing him to a four-year contract.

Stastny, the son of Peter Stastny, a member of the Hockey Hall of Fame, is from St. Louis. Peter finished his career in St. Louis, playing the final two seasons (1993-95). Paul's brother Yan also played for the Blues (2007-10).

Paul Stastny has played eight seasons in the NHL, 538 games, all with the Avalanche. He had 60 points (25 goals) in 71 games last season and has 458 points in his career, with 18 points in 22 games in the Stanley Cup Playoffs.

"It's a tough decision, [but] I was in a good position," Stastny said. "I think I had teams interested, good teams interested, and obviously the odds are always one of those teams in the end, you almost have to take a step back and take all the emotions out of it and try to realize what's best for me hockey-wise. Not just next year, but two or three or four years down the road. My family and my fiancée talked that by going to St. Louis, it would probably be the best hockey decision for me."

The Blues have David Backes and Stastny as their top-two centers to compete in the deep Western Conference, which has several contenders with elite players at that position. But Blues general manager Doug Armstrong, after also signing center and 2008 third-round pick Jori Lehtera to a two-year contract, said he can envision Backes moving back to his natural position at right wing.

"I see a scenario where Paul plays with [Alexander] Steen and Backes," Armstrong said. "That gives us quite a bit of strength on the wing, [and] the size with Backes. And then you have [Patrik] Berglund with [Vladimir] Sobotka and maybe [T.J.] Oshie as another line. Lehtera has a history with [Vladimir] Tarasenko from the KHL.

"We're not your normally defined first, second, third line. We're more of a group of nine forwards and I think our group of nine forwards is stronger [Tuesday] than it was [Monday]."

The Blues made Stastny a priority and aggressively pursued their target.

"I was certainly hoping that we were going to get into the final grouping," Armstrong said. "I was a little bit nervous [Tuesday] morning when Dallas made their acquisition and what our Plan B would be. We never got to there, but Paul was certainly someone that we had focused on. The five-day window of opportunity allowed us to speak to him, and then as the week progressed and there was no news that he had signed (with Colorado), we thought he was getting closer to the market, and we felt that if he [did], we'd be a very good fit for him.

"Obviously a lot of has been made of this is his home where he grew up. When you're a competitor like Paul and a free agent, you're looking for a chance to go where your team has a chance at success also. I felt we provided a lot for him on the ice."

The fact the Blues were one of the most aggressive teams and made Stastny their top priority may have simplified the decision to leave Colorado, where Stastny not only attended the University of Denver but spent his entire NHL career.

"It's almost like you're a college recruit," Stastny said. "Those first couple teams that go after you obviously have the most interest, and then obviously once other teams find out, other teams are interested and those teams come in later.

"[The Blues] were one of those early teams, and there was quite a few of those teams. Obviously that plays a big factor because you don't want to go somewhere where they come in late. I think you want a place where you're wanted. I think the Blues really showed that."

It made it an easier selling point to agent Matt Keator, who described the Blues' interest as very aggressive.

"His first choice was to be in Colorado," Keator said. "Colorado was great to deal with, but we just couldn't match up on a deal that made sense for both sides. When we turned our attention to the open market, it just more and more seemed St. Louis was the best fit and made the most sense. It's obviously his hometown.

"Because it's his hometown and because it's a Cup-contending team, Paul took a lot less money and a lot less term that he could have on the open market to sign there. He knows the Blues are committed to being a Cup-contender and he's excited to be there."

Stastny said a selling point to him was the Blues' defensemen, featuring Alex Pietrangelo, Jay Bouwmeester, Kevin Shattenkirk, Carl Gunnarsson, Barret Jackman, Jordan Leopold and Ian Cole. Playing with puck-moving defensemen fits Stastny's style.