Ex-Celtic star Darren Jackson believes Scotland boss Steve Clarke has missed a trick by refusing to bring "sensational" Billy Gilmour into the full squad.

Gilmour, 18, has started the season well for Chelsea and even managed to get some minutes into his legs in the first-team.

An English Premier League debut for the Blues at Stamford Bridge came for the kid against Sheffield United before he was handed his first start in the EFL Cup against Grimsby Town.

Billy Gilmour left out of Scotland squad to continue development with under-21s outfit

Manager Frank Lampard lavished the youngster with praise for his performance in the cup, insisting he "ran the show".

But Scotland boss Clarke decided to leave him with the under-21s to continue his development.

Jackson, though - who himself earned 28 caps for Scotland - reckons the double header against Russia and San Marino would have been the ideal time to blood Gilmour alongside fellow new boy Lawrence Shankland.

He told PLZ Soccer: "I've been lucky enough to work with Billy at the under-19s and the kid is sensational, he's incredible.

"Could he go into the squad? He'd relish it.

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"The thing is, it's probably the strongest point when you look at Armstrong who can't get in the squad.

"I'd have Billy in there and he'd do it no problem, he'd relish the challenge.

"You see him playing for Chelsea, I know what he's like in training and his desire in training was incredible."