Rangers GM talks Marc Staal

PHILADELPHIA -- New York Rangers general manager Glen Sather said he thinks defenseman Marc Staal will rejoin the team in Europe by the end of this week and questioned whether the headaches that are keeping Staal behind are even related to his February concussion.

"There are a lot of things that cause headaches. You can look at migraines -- you can have a slipped disk, you can have pulled muscles, you can have a hundred different things," Sather said after Monday's press conference at Philadelphia's Citizens Bank Park announcing this year's Winter Classic game between the Rangers and Flyers. "Trying to diagnose exactly whether it's a concussion or something else that's bothering a player, that's what you really have to find out first. And, that's been complicated."

Staal is still experiencing headaches, believed to be a lingering effect stemming from a concussion sustained last February. Playing it safe with their top defenseman, the Rangers decided Staal would not travel on the charter when the team heads overseas Monday night immediately following their 7 p.m. game against the Flyers.

The 24-year-old will stay behind and continue to meet with specialists and team doctors until his condition improves.

Despite the serious nature of these recent developments, Sather said he's "not concerned at all" about Staal, who suffered the concussion from a hit by his brother Eric during a Rangers-Hurricanes game Feb. 22.

"What I'm saying is that I'm not exactly sure and I've heard [the headaches] may not be [from the concussion]," Sather said. "It's such a fine area of trying to define exactly what's causing the problem."

Sather said he thinks the team has "a handle on it" now and should know more in the next few days. He also left the door open to bringing in a defenseman should Staal's condition cause him to miss a significant amount of time.

When asked about Staal's immediate plans, Sather predicted he will rejoin the team "probably Thursday or Friday."

Katie Strang covers the NHL for ESPNNewYork.com.