NICOLA Sturgeon has threatened to show football the red card if players continue to flout Covid guidance.

The First Minister said Celtic defender Boli Bolingoli had committed a “flagrant breach” of the rules by taking a secret trip to Spain then failing to quarantine for 14 days on return to Scotland.

Spain has been re-categorised as a high-risk country due to increasing levels of the virus, but the 25-year-old Belgian national came on as a substitute during the Parkhead side’s match against Kilmarnock on Sunday.

It comes days after eight Aberdeen players were condemned for breaking ‘sporting bubble’ rules to dine at a city centre pub, with two subsequently testing positive and six teammates forced to self-isolate.

All Aberdeen and Celtic matches have been postponed for the rest of this week, including the Celtic-Aberdeen clash which was due to take place on Saturday.

READ MORE: Aberdeen outbreak shows signs of slowing - amid mystery rise in Lothian hospital admissions 

Ms Sturgeon warned clubs that she was “drawing a line in the sand”, after Justice Minister Humza Yousef said the Scottish Government had been left “little choice” but to consider pausing the season.

Ms Sturgeon said: “Let me put this as clearly as I can in language the football world will understand: consider today the yellow card.

“The next time it will be the red card, because you will leave us with absolutely no choice.”

The First Minister said news of the latest controversy by Bolingoli had emerged while Scotland’s national clinical director, Professor Jason Leitch, was holding a briefing with all 12 SPL managers and captains on Monday night, reiterating the measures needed to ensure professional sport can continue safely.

Ms Sturgeon added: “This is just not acceptable. We are asking members of the public to make huge sacrifices in how they live their lives, and the vast majority of the public are doing that.

“We can’t have privileged football players just deciding they’re not going to bother. This can’t go on.”

Prof Leitch said Bolongoli had put public health at risk by his actions.

“This young man went to Spain, a high risk country that we have assessed you shouldn’t then go about your business as normal [after visiting] whether you’re a shop worker, a factory worker, or a footballer,” said Prof Leitch.

“He went to work and put both his team and the opposing team at risk of catching coronavirus. We have, at a public health level, to take that very seriously.”

It came as Dr Emmanuel Okpo, the consultant in public health medicine leading investigations into the Covid outbreak linked to dozens of licensed premises in Aberdeen, said it had been driven by “a lack of physical distancing”.

The city’s partial lockdown, which closed all indoor and outdoor hospitality venues last Wednesday and banned residents from travelling more than five miles for leisure or visiting other households indoors, will be reviewed tomorrow.

At present, 165 people had tested positive as part of the Aberdeen cluster - up eight in the past 24 hours - with signs of a “kind of slowing”, according to Prof Leitch.

“The Aberdeen semi-lockdown is doing what we expected,” he added, though Ms Sturgeon stressed that it “would be a mistake” to lift restrictions too soon.

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The outbreak was first identified among customers who had been drinking at the Hawthorn Lounge pub on July 26, but detections rapidly increased and more than 30 pubs, restaurants, cafes, hotels and sports clubs were linked to positive cases.

Dr Okpo said: “It is clear from our investigations to date that a lack of physical distancing has been the significant factor in the spread of these cases.

“While pubs and restaurants have guidelines to work to, to support physical distancing, it is also the responsibility of each one of us to keep our distance.”

Dr Okpo said staying at least two metres apart from others was “simple but incredibly effective” at curtailing the spread of the infection.

Pubs, restaurants and other hospitality businesses have been allowed to seat tables one metre apart after warnings from sector bosses that imposing a two-metre rule would be disastrous financially.

However, the guidance remains that individuals from different households should keep two metres apart where possible, and no more than three households should meet together indoors.

“The guidance on this has not changed," said Dr Okpo. "We need to keep a two metre distance from those not within our immediate household.

"This must apply at all times; at work, meeting other households (outdoors and indoors), when shopping, or when socialising.

"Keeping our distance is a simple but incredibly effective way to stop this virus in its tracks.”

In Scotland as a whole, 52 new positive cases were reported today - including 27 in Grampian.

READ MORE: How can we persuade the young to stick to Covid rules when they have so little to fear? 

Ms Sturgeon said public health teams were "looking very closely" 13 new cases in the Greater Glasgow and Clyde region, where there have also been six new Covid-related hospital admissions since Sunday.

NHS Tayside has also detected a cluster of five cases in north-east Angus - one directly linked to the Aberdeen outbreak. All five have mild symptoms.

Dr Daniel Chandler, NHS Tayside's associate director of public health, added: “There is currently no evidence of wider community spread in Angus or elsewhere in Tayside.

"No individual premises, businesses or establishments are currently linked to the ongoing investigation."

Prof Leitch said he would also seek clarity on the situation in Lothian, where the number of patients in hospital with Covid has increased by 12 since July 28 - a trend not seen in any other health board area.

The region has not had any significant spike in cases.

Prof Leitch said: "It may be that in Lothian it is older patients who've been testing positive and therefore had a sicker journey than those areas where younger people are getting infected.

"In Grampian, we haven't seen the expected number of hospitalisations for the numbers there because it is mainly in young people."