The teenager was a half-time substitute but was forced back off after Luxembourg replacement Oliver Thill smashed into him in a powerful mid-air clash.
Gilmour had excelled on just his second international outing and caught the eye during his 20 minute cameo. Clarke, who hails from Saltcoats just a couple of miles along the west coast from Gilmour’s Ardrossan upbringing, hoped it wouldn’t overshadow his side’s lead into the Euro’s next week but was pleased his players rallied round in the aftermath.
Scotland players were incensed by the lunge where Thill’s shoulder collided with Gilmour’s head and Clarke took the safety-first option and sent on James Forrest to let his Champions League winner shake it off in the stand – much to the midfielder’s frustration.
Clarke said: "The good news is he's fine. We took him off as a precaution and the doctors will assess him over the next couple of days but I’ve spoken to him. He’s a tough boy, he’s from Ardrossan and he’s fine.
"I didn’t get a good view of the challenge but it’s one of these things that happen in football – but the reaction of the players was good, getting around for a bit of protection and it showed we are altogether.
"But let's not make that the big story – the big story is we are now fully prepared for our first tournament in 23 years, so lets look forward to it.”
Scotland won 1-0 thanks to Che Adams’ first-half goal.