Callum: We will take out our Buddies frustration on old foes Rosenborg

They’re used to floating into Europe on a cloud of domestic bliss. Now Callum McGregor insists Celtic will take the frustrations of Friday out on old foes Rosenborg.

The champions fell five points behind Hearts at the top as St Mirren held them in check, their edginess evident at more points dropped away from home.

Celtic’s task was made even harder following a first- half red card for midfielder Olivier Ntcham.

And McGregor admits they were knocked off stride by a Saints side desperate to impress their new boss.

The previous 22 times Celts have gone into continental battle under Brendan Rodgers, Celtic won 19 times going in – but the three they haven’t have all been followed by defeats.

And McGregor confessed: “It was tough. When you go down 10 men you have to try to find a way to win.

“While we dominated possession in the second half, we just couldn’t find a goal. It just wasn’t falling for us.

“They were playing for their point and especially when we went down to 10 men it was a great opportunity for them just to hold on.

“You have to give them credit, they were tight all night and the new manager came in to give the players a lift.

“Can we get the frustration out of our system for Thursday though?

“It’s difficult, the first game back from internationals. Everyone’s away playing different systems so to get everyone back in can be hard. But we’ll try to take positives out it for Europe.

“It was frustrating, which you get when you come to places like