Heard the one about the striker who took a fortnight off to get fit? He came back injured.

There were no belly laughs, however, as Celtic manager Brendan Rodgers explained that Leigh Griffiths is not expected to feature against Hibs this afternoon after the striker’s efforts to put his body through its paces were derailed.

“He’s not available,” said Rodgers. “Leigh got injured early on in the break and now he’s ill. It was a slight issue with his calf, so we shall see.”

If it was difficult to ignore the terse nature of the delivery, it is of little surprise.

It has been a familiar line since Rodgers took over at Celtic Park with the staccato nature of Griffiths’ appearances under the 45-year-old telling. The striker can draw his stats around him like a protective cloak whenever the flak comes – the first Celtic player in 13 years to score 100 goals from the club highlights the instinctive nature of his ability – but there is a sense that his lifestyle is a source of perennial frustration to his manager.

“I don’t cry on about it all the time but we have a top level sports science team here that measure and monitor and a coaching programme that will develop players in every aspect – technically, tactically, physically, mentally,” said Rodgers. “If you throw yourself at it there is every chance you will improve. We create the environment and 99% of players want to improve, they want to get better. If you are one of those you will get better because the environment allows you to do that and it is something that he is recognising.”

Asked of the penny had finally dropped with Griffiths, Rodgers shrugged: “We will see. It’s always revealed on the pitch.”

Not that he was critical of the decision to walk away from international duty.

Griffiths spoke to Rodgers before informing Scotland manager Alex McLeish of his intention to return to Lennoxtown to train, a decision that the Celtic manager believes was the correct call. But as Rodgers expanded on his belief that taking to a field without ample physical preparation sells people short there was the recurring feeling of a rebuke as he offered his take on the situation.

“You have no business being on a pitch if you are not physically right,” said Rodgers. “And I have said that since the first day I came in here. You have no business being on a football pitch. You have supporters who give their lives to follow their team and follow their country and some not earning anywhere near the money that footballers will make.

“The bare minimum requirement is that you are physically fit. Leigh was brave enough to recognise that he was not. So he has to do something about it. I thought it was the right decision. In modern day football, it’s not just about scoring goals. If you can’t press the game at the top of the pitch because you can’t run, it has a knock-on effect for the team. It was the right decision.”

Meanwhile, Rodgers has also offered his own case for the fact that Australian teenager Daniel Arzani has yet to feature for the senior team since arriving on a two-year loan deal from Manchester City in August.

There has been a lot of noise regarding the winger’s lack of exposure at Celtic but Rodgers remains relaxed as to the overall development of the player. Celtic rubbished claims this week that there was an exit clause to release Arzani back to parent club Manchester City if he had not made the first-team breakthrough by the end of November with Rodgers offering an explanation as to why he has not been particularly visible since his arrival.

“He is a 19-year-old boy who has come in for two years to get experience,” he said. “He has burst onto the scene and of course they will want him to do well.

“But there is no exit clause. He has adapted very well and much as people would love him to come in and play he wasn’t ready. It’s all a process. He came in after a World Cup with players a number of weeks ahead of him in terms of fitness and training.

“He is adapting to a more physical game. There are lots of things but he is very happy and we have been very pleased in terms of how he is making progress. It’s not easy to just snap your fingers and just come into a top team with top players who have done very well.

“But I have been really pleased with how he is developing and working and adapting to how we want to work. It’s a really good education for him.”

Celtic’s game against Hibs is a sell-out, with Rodgers keen to pick up where he left off at McDiarmid Park before the international break. The 6-0 win over a hapless St Johnstone side was the most fluid and potent Celtic have been in a season in which they have been uncharacteristically flat at times.

“It hasn’t always been like that for us this season for various reasons,” said Rodgers. “But this is the key to coaching and working with players – you can never get frustrated with them. You will get frustrated with other things but if you are going to develop and improve them then you can never get frustrated with players. Slowly you see now the flow of our game coming back.”