A Scots father and his two sons have been left 'shaken' after being attacked by a gang of Atletico fans in a Madrid bar ahead of tonight's 'high risk' Champions League match against Celtic.

Mark O'Donnell, 61, told how he was watching football in a pub in the Barrio of La Latina district on Monday's night, with his two sons when a gang of around 20 rival supporters came into the bar.

He said one of the fans asked 'Are you Celtic?' and the family, who support the Glasgow club, were then subjected to an unprovoked attack.

All three suffered cuts and one of his sons was taken to the Hospital Clinico San Carlos and received eight stitches to a wound in his hand. 

The Herald: Mr O'Donnell's son was treated for a hand woundMr O'Donnell's son was treated for a hand wound (Image: family)

Mr O'Donnell speaks Spanish and called local police who sent an ambulance to the bar for his son, who is in his early twenties and is a product design engineer. He said they were very shaken after the incident. His sons did not want to be named in the article.

"We were in a bar watching the Tottenham game when about 20 Atletico fans came in," said Mr O'Donnell, who lives in Glasgow's west end.

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"One of them said 'Are you Celtic?' and then they attacked us. I have cuts to my leg and hands, one of my sons has cuts to his head and the other received eight stitches for cuts to his hands.

 "He met another man in hospital older than me who was also attacked. He had been hit in the face with a bottle and had to have numerous stitches to his face."

The family was enjoying a four-day break in the Spanish capital that had been planned for months to tie in with the match. More than 3,300 Celtic fans are thought to have travelled to Madrid for the game.

The two clubs have a long rivalry following a match in 1974 which became known as the 'Shame Game'.

The Herald: Celtic midfielder Paulo Bernardo enjoyed a fiesty midfield battle against Atletico Madrid.

They met in the European Cup semi-finals, with Atletico progressing 2-0 on aggregate.

The first leg in Glasgow finished 0-0 and has gone down in history for all the wrong reasons.

The referee dished out 11 yellow cards and three red cards as the Spanish side "kicked lumps out of their opponents".

READ MORE: Atletico manager raves about Celtic 'intensity' ahead of crunch match 

Atletico had already picked up four yellow cards inside the opening 20 minutes and they were down to nine men just ten minutes into the second-half.

Celtic icon Billy McNeill described Atletico as "the scum" of Europe following the match.

Ruben Diaz, one of the players dismissed, remarked some years later that he deserved to be jailed for his tackles on Jimmy Johnstone.

Atletico would go on to win the second leg 2-0 and progress to the final, where they'd lose out to Bayern Munich.

Tonight's game at the Metropolitano Stadium has been classified as 'high risk' according to reports with more than 1,300 officers from the National Police Corps, Municipal Police, Civil Protection  deployed to monitor the areas surrounding the stadium to prevent incidents.

Celtic currently sit bottom of Group E with three games to play, having picked up their only point in a 2-2 draw with the Spaniards in Glasgow. 

Police said five men were arrested and charged in connection with acts of disorder at the game.

Unbeaten Atletico are second on five points from their opening fixtures.