Ashen-faced Callum McGregor warns Celtic 'embarrassing' defeat against Atletico Madrid MUST be a one off

Callum McGregor has warned his Celtic team-mates that their "embarrassing" six goal hammering at the hands of Atletico Madrid MUST be a one-off.

The Hoops' hopes of making it out of Champions League Group E and hanging by a thread after their mauling in Madrid. Daizen Maeda's controversial first half red card played a big part in the outcome, but Atleti simply toyed with the Scottish champions, having already been 1-0 up after six minutes before the visitors went down to ten.

Antoine Griezmann and Alvaro Morata ran riot as the scoreline was racked up after the break. Diego Simeone's men hit another four without reply as Celtic's wait for a first win on Spanish soil. as well as this season's campaign, goes on. McGregor refused to blame Maeda after the final whistle, bit warned they have to learn lessons fast after ending another game at this level without a full complement.

He told TNT Sports: “Embarrassing to lose six goals. We have to learn quickly and make sure that’s a one-off. It’s difficult enough XI vs XI but that’s not to point fingers. There have been challenges over the two games but there’s not not been any malice in them. The threshold is so low now we have to adjust how we’re defending. This level is too difficult to play with ten men or nine men.”