INJURY is the curse of every active sportsperson, and this week it might also prove a major setback to the hitherto glittering career at Celtic of manager Brendan Rodgers. And he’s not even the injured one.

Robert Burns called toothache the “hell of all diseases” in which case a torn calf muscle as suffered by Leigh Griffiths is the purgatory of sports injuries, and there might well be tears in Paradise if the hero of Scotland’s last international match doesn’t get fit by tomorrow night for the second leg of the Champions League qualifier against Rosenborg.

Wedded as he is to the lone striker system, Rodgers has been able to use either Moussa Dembele or Griffiths in that role and both contributed wonderfully to Celtic’s invincible domestic campaign last term. Now both are injured, and Dembele is definitely out for at least a month while Griffiths faces a real struggle to recover from that calf problem to make the match in Norway.

It might all work out with Griffiths being able to play, but if not, Rodgers will have to rely on a makeshift striker such as James Forrest, Jonny Hayes or Callum McGregor, though Scott Sinclair might well be asked to play up front where he did not exactly shine in the home tie.

The alternative might have been to play the only other definite forward in Celtic’s first-team squad, namely Nadir Çiftçi. But he is on the way out of Parkhead and wasn’t even registered to play in Europe on the List A squad sheet which every club must register before each qualifying round.

Otherwise Rodgers will have to vary his playing system and that’s a monumental risk for a match that Celtic must win if they are to have even a chance of making the tournament proper.

I have to question why Celtic are in this position. The group stage is worth tens of millions to the club, and there was always the risk of Griffiths and Dembele getting injured. I know Rodgers has said categorically that Scottish Premiership clubs can’t afford quality strikers who will simply sit at home or on the bench and wait until someone gets injured.

However, the point is that Celtic see themselves as a club who should always feature in the Champions League or at least the Europa League group stage, and even the latter might be out of reach for Celtic if they cannot solve the striking conundrum.

Rodgers and his scouting team should have been out looking for a proven striker, even for a short-term loan. That could have worked for both player and club as the striker would get to put himself in the shop window and Rodgers would at least have had cover in such a vital position. Uefa’s arcane squad registration system allows for just such an eventuality as a “wildcard” player can be drafted into the List A squad up until 11pm the night before the match is played.

Should Griffiths not be fit and should Celtic not prevail against Rosenborg, questions will undoubtedly be asked as to why the Scottish champions simply didn’t have enough firepower up front.

Still, injuries happen to all clubs, and Rosenborg’s very experienced Norwegian international defender Tore Reginiussen will be missing after failing to recover from the thigh injury he sustained at Parkhead.

However, that may not be enough to cancel out the absence of Dembele and Griffiths and Celtic really are walking a tightrope tomorrow night. They are not alone in the world of Scottish sport.

Sometime soon, Andy Murray is going to have to decide if he will follow the lead of Novak Djokovic and take an extended break from tennis to allow his hip injury to heal.

Rafael Nadal and Roger Federer have also had to take time out mid-season in recent years due to the stresses and strains playing top rank tennis causes to the body.

So will Murray decide that hanging on to his world No 1 position and foregoing the chance to win the US Open is worth it?

He will be 31 in January, the same age that I was when a surgeon advised me to curtail my less than glittering rugby career. I still loved playing the game but when he handed me a test tube with bits of white stuff floating in it and said “that’s what was left of your cartilage” I knew that the Lismore 2nd and 3rd XVs would have to do without my presence from then on, though I did make the odd comeback and even played a game at the age of 40 – took me weeks to walk properly afterwards.

Such was the wear-and-tear arthritic damage that I had to have my knee replaced nearly two years ago, and I have since been asked on several occasions: “If you had known you were going to be virtually crippled at the age of 55, and would need a painful knee replacement operation, would you have played rugby at all?’ Without hesitation, I always say yes, and add I just wish I had trained more and been fitter because that is the way to avoid serious damage to your joints as a young person.

Injury is part of sport at all levels, and in the professional games and increasingly in the amateur ranks of many sports, there are specialists who treat sports injuries capably and well.

Yes, there can be catastrophic injuries in sport, some life-changing, but on balance I would always favour youngsters in particular playing games such as football, rugby, and tennis. For most of gain so much more than we lose from sport.

Now come on Celtic and Aberdeen and keep Scotland in Europe so that I don’t have to write the column the SPFL and SFA are dreading. Och, I’ll write it anyway, for it’s about a cause dear to my heart – summer football.