LEIGH Griffiths last night hit back at accusations the Celtic players have contributed to the downfall of Ronny Deila by failing to fully embrace his strict fitness regime.

Griffiths and his team mates were severely criticised for not being fit enough in the William Hill Scottish Cup semi-final defeat to Rangers at Hampden on Sunday.

The Parkhead club lost 5-4 on penalties to their Old Firm rivals after the game had finished tied 2-2 after 120 minutes – a result that led to Deila standing down as manager.

There have been suggestions that many squad members have rejected the diet and conditioning programme the Norwegian coach introduced after he was appointed two years ago.

However, Celtic’s leading goalscorer, who has netted 37 times in all competitions this season, has dismissed those claims.

“For people to say we’re not fit enough is b*****s in my opinion,” said Griffiths.

“Yes of course, it’s us, at the end of the day, that’s out on the park trying to get results and at times the results haven’t been good enough.

“But we ran for 120 minutes on Sunday and at the end of games we’re still pressing on when other teams are dead on their feet. That’s why we’ve got some late goals this season.”

Griffiths, though, has admitted that some players in the Celtic squad wouldn't be too distraught to see Deila depart at the end of the 2015/16 campaign.

“That’s part and parcel of any dressing room,” he said. “People will not be in favour, people will be in favour. With the new manager coming in now everyone has got a clean slate and it’s up to them to go and impress.”

Neil Lennon, the former Celtic manager who signed Griffiths from Wolves for £1 million in 2014, admitted this week he would welcome the chance to speak to the Parkhead board about Deila's position.

The Scotland internationalist believes the Irishman, who won three Scottish titles, beat Barcelona and qualified for the knockout stages of the Champions League during his time in charge, will be a strong contender for the vacancy.

However, Roy Keane, Henrik Larsson, Davie Moyes, Michael O’Neill, Brendan Rodgers, Alan Stubbs and others have all been linked with the job and the 25-year-old reckons it will be of great interest to many managers.

“Managers who are not in a job will be delighted to have their name associated with this club,” said Griffiths.

“I think any manager being linked with the Celtic job will be happy. The club is massive. It is the biggest club in Scotland in my opinion and one of the biggest in the world.

“We have a lot of fans and the manager coming in will want to turn this job around and make us a Champions League team again.”

He added: “Lenny has been associated with Celtic one way or the other for the last 15 years. The fact he is not in a job now gives him a good chance.

“But there are other managers, big name managers out there out of work and looking forward hopefully to getting an interview.

“It’s entirely up to the board, whoever they decide to bring in. There are managers who aren’t in a job right now licking their lips at a chance of the Celtic job.”