SCOTLAND were dealt a bitter blow in their quest to reach the knockout stages of a major tournament for the first time after Billy Gilmour returned a positive test for Covid-19 on the eve of their do-or-die clash with Croatia.

A victory for Steve Clarke’s players should be enough to take them into the last 16 but that task has been made all the more difficult now that Gilmour is unavailable, particularly considering the 20-year-old’s man of the match performance against the Auld Enemy at Wembley on Friday night.

The positive test means the Chelsea playmaker is self-isolating for the next 10 days – ruling him out of the Croatia game and any potential last-16 tie, should Scotland make it out of the group – but it does not necessarily mean that the youngster’s tournament is over.

HeraldScotland:

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Have there been other cases?

Gilmour isn’t the first player to test for Covid at the Euros. Spain have perhaps been affected more than any other side at the tournament and have not had their problems to seek. Midfielder Sergio Busquets tested positive for coronavirus eight days before their opening fixture, forcing the entire squad into self-isolation for their final warm-up game as they had been identified as close contacts, with the Barcelona player expected to make his return for their final group stage fixture against Slovakia.

Leeds defender Diego Llorente was allowed to rejoin the squad after an initial test returned a positive result but after four subsequent tests it was revealed that it was a false positive.

Slovakia have had Covid problems of their own after Lazio defender Denis Vavro and a member of staff returned positive tests late last week and had to self-isolate.

Manchester City full-back Joao Cancelo was dropped from Portugal’s squad altogether after testing positive for the virus earlier this month, as were Netherlands goalkeeper Jasper Cillessen and Russia midfielder Andrey Mostovoy.

However, there is no risk of Gilmour being dropped from the squad and a replacement being drafted in. UEFA’s rules state that any player who tested positive for Covid before it started could be taken out of the team and a new player called up but once the tournament began, the squads are largely set in stone – the only exception being if a goalkeeper contracts coronavirus.

Matches can be postponed but this will only happen in extreme circumstances where a squad is decimated. So long as a team has 13 players available, including a goalie, fixtures are expected to go ahead as planned.

READ MORE: Euro 2020: Billy Gilmour ruled out of Scotland v Croatia after testing positive for Covid

How does this affect Scotland?

Thankfully, it doesn’t look as bad as it could be. Gilmour is out but no other player has been identified as a close contact and the remaining 25 members of the squad trained as usual on Monday morning.

Some supporters were concerned after footage emerged of Gilmour playing table tennis with team-mates Andy Robertson and John McGinn on Sunday evening with the Liverpool full-back then deleting the video from his Instagram page the following day after the Scottish FA’s announcement. A standard ping-pong table is 2.74 metres long – exceeding the Government’s social distancing guidelines.

A spokesman for the SFA said: “We’ve been in discussions with Public Health England and no close contacts have been identified.”

Six Scotland players – David Marshall, Grant Hanley, Nathan Patterson, Stephen O’Donnell, John McGinn and Che Adams – were unable to travel to Portugal for the final warm-up fixture against Luxembourg after Sheffield United midfielder John Fleck tested positive for Covid at the start of June, although this was seen as a precautionary measure as Fleck only returned negative tests thereafter.