The saddest part of Carlos Tevez's apparent refusal to play in Munich on Tuesday night was that, physically, there was nothing to stop him. Apart from being supremely gifted, the Manchester City forward is also healthy and fit. How those players recovering from serious injuries, such as Jack Wilshere, Stuart Holden and Tom Huddlestone, must have wanted to hurl a crutch through their TV sets.

It is hard enough to miss out on a place in the team through merit, but at least the chance of getting some match time remains a possibility when you are fit. Spirits can also be kept high from training and mixing with the squad in the usual way. There is, however, no consolation when you are sidelined with an injury, especially when it is a serious one. From the loneliness of the treatment room to the reaction of your peers (who on the rare occasions that you bump into them talk to you as if you have some kind of incurable disease), being injured is a thoroughly miserable experience.

The monotony that accompanies months of rehabilitation is enough to send a player over the edge. The best physios I have worked with are the ones that treat you on a one-to-one basis, engaging in your recovery and talking you through every step. The worst physio I ever had used to hand me the same sheet of paper every day with an upper-body weights circuit written on it before wandering off around the training pitch all morning watching five-a-sides. I may not be a medical expert but I know that bench pressing your own bodyweight every day for a month is no cure for a torn hamstring.

There are times when you can be made to feel guilty if you are injured, and more than one manager I played under made the conscious decision to move the gym as close as possible to the training pitches, so that those players undergoing rehab would do so staring at their team-mates running around without a care in the world. It may have been paranoia on my part brought about by not playing, but I'm sure the coaching sessions looked twice as much fun as they were when I was involved. Had I not had something to focus on every day, I think I could well have lost my mind under an avalanche of core balls and treadmills.

Even today, with so much medical knowledge at hand, there are a number of managers who are deeply sceptical when it comes to passing judgment on whether or not a player is genuinely injured. It is, though, true to say that some players appear to have a lower pain threshold than others, for even the slightest of knocks. In fact, if one were to look at a few of them through the eyes of an experienced manager then it might be argued that some players are suffering from nothing more than a metaphorically weak heart.

For the record, feigning injury, or "throwing one in", as it is often known, is one of the worst things that a player can do in the eyes of his fellow pros. Fortunately, I have only encountered it a small number of times and on each occasion the player in question was never treated with the same respect again. Anyone wondering how an injury can be disproved would do well to bend the ear of a disgruntled physio whose professionalism and loyalty are being severely compromised by a player trying to pull a fast one.

There are, of course, financial implications to being injured but missing out on bonuses and appearance fees are part and parcel of not playing anyway. And while Premier League players won't necessarily have to fend off their bank managers, there are many lower down the leagues for whom injury can severely compromise their financial position.

Conversely, I know one or two players who have lost out on huge contracts – we're talking tens of thousands of pounds a week – because they have suffered an injury in the middle of negotiations. Although it is often possible to return to peak fitness, they are not always able to get back to the boardroom table with quite the same bargaining power. Not that it is all about money. Whenever I have been injured my first thought has always been: "How long until I can play again?" And I genuinely believe that is the case with 99% of players.

Our greatest fear is that we will go through the same sort of experience as the friend of mine who will probably be reading this column in a taxi. A serious knee injury just as he was about to sign his first big-money contract ultimately put paid to his football career and forced him to find gainful employment with the local cab firm. Most players know someone with a similar story, yet it doesn't always stop them from taking a risk by cutting corners with their private medical insurance.

At least my friend knew when to stop playing, doing so before he did his body any real long-term damage. While I feel a great deal of admiration for the attitude and determination of players such as Owen Hargreaves to ultimately prevail, the lasting effects on a body that takes such a battering from the demands of top-level football makes me anxious, from a health point of view, for their future quality of life.

The highs of football are more than matched by the lows, and they don't get much lower than being seriously injured with all the time in the world to battle against the negative thoughts going round in your head. Football can often become routine and sometimes you really don't appreciate what you have until somebody takes it away. If the prospect of playing against Bayern Munich in the Champions League no longer does it for Tevez, then I'd hate to see him staring at the same four walls in the treatment room.

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