I told Arne Engels after joining Celtic his one-game-a-week holiday was over – The brutal rules for £11m man

Brendan Rodgers has told his Celtic stars to keep grafting as Parkhead is not a holiday camp.

The Hoops face Dundee United on the back of a lung busting run of 16 games across three competitions in just two months since the Premier Sports Cup Final win against Rangers. Rodgers’ men are also gearing up for the crunch Champions League play-off second leg against Bayern Munich in Germany on Tuesday.

Midfielder Paulo Bernardo will miss the trip and is facing up to five weeks out with an ankle injury – but winger James Forrest is back in training after 10 weeks out. The Celtic gaffer will rotate for United but he has warned it will be all hands to the pump as his side chase a domestic Treble and glory in Europe. Rodgers said: "It's been a really unrelenting schedule but the players have been brilliant. We're ready. You have to be. It's not a case of you won't be tired, you will have moments of tiredness.

"But that's being at a big club. I said to Arne Engels when he came in at the beginning, his one-game-a-week holiday was finished at Augsburg. Now he was coming into a big club where there's no holidays here.

"He now knows what I was talking about. He and all the players have been absolutely brilliant. Being a top player is about managing fatigue, managing the tiredness.

"Because you have to deliver. And that's what it takes to be at a big club. Otherwise, you go and play one game a week somewhere else and it's quite nice.”

Rodgers will mix it up for United though with Bayern in the back of his mind. He said: “We’ll do what we've done most of the season. There's some areas we'll freshen up where we need to. Of course you can't not look at Tuesday, because the turnaround is so fast.

"But, I also know for the bread and