Callum McGregor says Celtic will have to “dig in and fight” to bounce back from defeat at Dens Park and show they are good enough to retain their Premiership title.

The champions fell five points behind league leaders Hearts over the weekend after suffering a 2-0 defeat to Dundee in Tayside.

It has been a shaky start to the season for Celtic who will need a result at Tynecastle next weekend to avoid slipping even further away in their quest for five in a row.

Before that they return to Europa League action as they look to get their first win on the board after a draw and a defeat from their opening two league phase games.

The Hoops skipper insists they now have to sharpen their focus and react to Sunday’s defeat with improved performances and results.

He said: “It was a poor afternoon, and a really poor result, it can’t happen at a club like Celtic, and it doesn’t happen too often to be honest.

“When you have a performance and a result like that, then I think it emphasises everything that has happened between since the start of the season.

“There’s only one way out of it and that is digging in and fighting...