But Clarke is prepared to utilise the marksman off the bench in Belgrade if Scotland need a goal and Reid can see why following his first experience of working up close with the striker, who has netted crucial goals against St Johnstone and Aberdeen as a substitute for Celtic in recent weeks.

After Griffiths reported for training on Monday morning, Reid said: "It was a smaller training session but you see glimpses, you see it all the time, those moments of quality that might be needed.

"His finish against Aberdeen took my breath away, the shift and the finish into the top corner.

"That's what he offers, that's what I have seen, that's the quality he has, which has never been in doubt, it's just about the consistency and the amount of minutes he has played and getting back up to match speed. But the quality is there and it was a pleasure to see some of his touches and finishes."

The reintroduction of Griffiths comes as a vacancy for a forward role emerged following confirmation that Ryan Fraser's hamstring injury would rule him out of the squad.

Serbia have also had selection issues with a positive Covid-19 test ruling out Sassuolo midfielder Filip Duricic, who netted both goals when the teams last met in 2013.

However, four other Italy-based players have joined up with the squad despite reports that coronavirus travel restrictions would rule them out.

Inter Milan defender Aleksandar Kolarov and Lazio midfielder Sergej Milinkovic Savic arrived in Belgrade early on Monday after getting round the rules.

And they were followed by Fiorentina pair Nikola Milenkovic and Dusan Vlahovic late on Monday night.

A statement on the Serbian football association's Instagram account read: "The huge effort of the Football Association of Serbia paid off in the end!

"After a few days of great struggle, it was possible for Nikola Milenkovic and Dusan Vlahovic to arrive in our country late Monday night and join the national team in the preparations at the sports centre of the Serbian Football Federation, so they will be available to coach Ljubisa Tumbakovic in the game against Scotland."