Calgary's Dion Phaneuf, left, was levelled during Game 5 and won't be in the lineup Monday against Chicago. ((Nam Y. Huh/Canadian Press))

Calgary's hard-hitting defenceman Dion Phaneuf won't be in the lineup Monday when the Flames play a must-win game to keep their playoff hopes alive against Chicago, coach Mike Keenan announced.

"He is not available," Keenan told the Calgary Flames' website. "And his status is day-to-day"

Phaneuf, who's out with an undisclosed upper body injury, joins a list of injured Flames players that includes fellow defender Robyn Regehr.

A Norris Trophy nominee last year for the NHL's top defenceman award, Phaneuf was levelled by Chicago's Troy Brouwer in the second half of the third period in Game 5, a 5-1 rout of Calgary.

The win gave the Blackhawks a 3-2 series lead in the western conference quarter-final.

Phaneuf wobbled over to the Flames bench and didn't return to the game. He did not take part in Monday's morning pre-game skate, and wasn't available to speak with reporters.

The six-foot-three, 213-pound defender led the Flames in hits during the regular season. He was also seeing the most ice of any Flame during the playoffs, averaging just shy of 25 minutes per game.

"It's not a good feeling, especially when a guy logs as much ice as he does," teammate Cory Sarich told the Flames' website. "But at the same time you can't sit there and dwell on it, you've got to concentrate and do your job and make sure you do it a little better than you normally do."

Phaneuf had three assists in the first five games of the series.