ESPN NHL

With the regular season coming down to its final days, there's virtually no margin of error left for the Chicago Blackhawks if they want to defend their Stanley Cup championship.

With nothing left to play for, the St. Louis Blues would simply love to walk into the United Center and play spoiler.

Before focusing on two games against their archrivals that may ultimately decide their season, the Blackhawks on Wednesday night host the Blues, who have been scoring in bunches on the road lately while playing out the string.

Last year, Chicago won its first title since 1961, but just getting back to the postseason is proving to be a difficult task.

The Blackhawks (42-28-9) picked up a key point with a 2-1 overtime loss to Montreal on Tuesday to tie Anaheim for seventh in the Western Conference with 93 points -- two ahead of Dallas and Calgary.

The Ducks, Blackhawks and Stars have three games remaining while the Flames will play just two.

Chicago will close the regular season with a home-and-home series against archrival Detroit starting Friday, but must face the Blues first.

The Blackhawks have taken three of five from St. Louis this season, including both matchups in Chicago. Overall, they have won three straight and five of six at home from the Blues, who will miss the playoffs for the fifth time in six seasons.

Heading into their season finale away from home, though, St. Louis (37-33-10) has scored 22 goals in three straight road wins, including 10-3 over the Central Division-leading Red Wings on March 30.

While the Blackhawks picked up a point in the loss to the Canadiens, Chicago could have helped its own cause with a win past regulation. Captain Jonathan Toews was given a penalty 37 seconds into overtime for tripping P.K. Subban, who scored 42 seconds later.

"It's more frustrating than heartbreaking," Toews said. "We worked so hard out there, then you try lifting a guy's stick and it ends up costing you the game. In overtime it's 4-on-3, it's a big difference. I was obviously not happy with that. It's frustrating when you're the guy that takes a penalty like that, but what can you do?"

Toews could get the chance to make amends. He has a team-high seven points in five games versus St. Louis this season, with all three of his goals coming on the power play. Patrick Kane and Marian Hossa also have scored three times against the Blues in 2010-11.

The Blackhawks have managed a total of one goal in their last three losses.

Meanwhile, the Blues won for the fifth time in seven games Tuesday, 3-1 over lowly Colorado as both teams combined for 132 penalty minutes.

David Backes reached the 30-goal mark for the second time in his career, and Kevin Shattenkirk haunted his old team by breaking a 1-all tie. Andy McDonald added an empty-netter for his 20th goal.

Backes, T.J. Oshie and Alex Pietrangelo are tied for the team lead with five points against Chicago this season.

St. Louis closes its season Saturday versus Nashville.