How serious is Mark Giordano’s injury?

Watch as Calgary Flames captain Mark Giordano is injured as the Flames score an empty net goal against the New Jersey Devils.

The signs are anything but positive.

Two days after their captain and best player, Mark Giordano, suffered an undisclosed injury, the Calgary Flames released a vague update on his health.

All we know for certain: He won’t play tonight, and his injury falls under the “upper-body” category.

Friday morning, the Flames recalled defenceman Tyler Wotherspoon from AHL Adirondack in advance of the club’s game against the Islanders in Long Island, N.Y.

General manager Brad Treliving appeared on Sportsnet 960 The Fan Friday morning and said that the all-star is still undergoing evaluation by the team's medical staff. There is no timeline for his return.

"If Giordano is out, you can't replace him," defenceman T.J. Brodie told reporters Thursday. "You just have to do all you can."

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Giordano was injured in the final seconds of Wednesday’s win in New Jersey when he was knocked down to the ice awkwardly by New Jersey Devils forward Steve Bernier. He headed right to the dressing room. (Watch the play above.)

"We want to make sure we're being diligent in terms of the protocol on all of the medical side of things," Treliving told reporters Friday. "Once we know where Mark's at, definitively, we'll share that... there's still some things [we] have to go through here."

The Flames (33-24-4) sit one point behind Minnesota for the Western Conference’s final wild-card spot, and a long-term injury to their best player could have an affect on how Treliving approaches Monday’s trade deadline.

The 31-year-old is a Norris Trophy candidate this season with 11 goals and 36 assists in 60 games. He is tied for the league lead for points by a defenceman.

Wotherspoon, Calgary’s second round pick in the 2011 NHL Entry Draft, has played 46 games for Adirondack this season, recording 21 points.

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