ST. LOUIS — The Ottawa Senators are playing the waiting game with Clarke MacArthur.

The winger was scheduled to make this three-game road trip but was left behind in Ottawa to undergo further testing to determine what’s next in his recovery from post-concussion syndrome.

MacArthur hasn’t played all season and underwent a three-hour baseline test Friday to see if he’ll be able to get clearance to return.

Coach Guy Boucher told reporters Tuesday morning during the club’s optional skate at the Scottrade Center that MacArthur requires more tests before a determination is made on whether he can continue his career.

“There was tests and everything but now they need to move to the next steps,” said Boucher before facing the St. Louis Blues. “I’m a bit lost in it, to be honest. For me, it’s, ‘OK, is he with us? Is he not with us?’ I’m dealing with it when he’s here. You’ve got to deal with the guys who are here and the task at hand.”

Boucher said he received an update after practice Monday from GM Pierre Dorion but no decisions have been made on when, or if, MacArthur will be able to come back. That’s what the Senators are trying to decide.

MacArthur suffered his fourth concussion in 18 months in camp and hasn’t played since Oct. 14, 2015. The doctors are being cautious because of the risks involved if he does return and that’s why no decision has been made.

Boucher isn’t willing to share a lot of information.

“I’m not touching it right now because I’m really focused on the guys that are here. The (front office will) keep me up to date,” Boucher said.

bgarrioch@postmedia.com

Twitter: @sungarrioch