Kris Commons is a doubt for Scotland's game against Denmark on Wednesday after suffering a foot injury in Celtic's win over Aberdeen.
The Scottish Football Association has confirmed the midfielder has returned to his club for treatment on the problem.
He turned up at Scotland's team hotel wearing a protective boot and will be given an opportunity to prove his fitness ahead of the Denmark friendly.
Scotland assistant manager Peter Houston said: "He's not out of the squad yet.
"There's a huge improvement from yesterday. He's coming back in tomorrow to be reassessed."
Scotland boss Craig Levein is unlikely to call upon a replacement for Commons, should he be unable to play.
Houston added: "We're happy with the squad and the boys are happy to be here as well."
Houston praised Commons' desire to join up with the squad, with internationals in the past for many nations afflicted by call-offs.
He continued "Too many times in the past players have called off easily - these players don't call off easily.
"The perfect example was today - Kris Commons turning up with a boot on his foot.
"He took a stud on the instep of his foot and turned up today.
"We thought, when he turned up with that on, he'd be ruled out, but he told us he wants to give it until tomorrow, every chance.
"That tells a lot for a friendly match. They've bought into the way Craig wants to build a unity in the squad."
Alan Hutton and Steven Whittaker withdrew from the squad on Sunday, with Cardiff duo Don Cowie and Kevin McNaughton called up as replacements.