No-one will be more upset with Andy Murray's withdrawal from the ATP World Tour Finals than the guy himself. It's a horrible way to finish the best year of your career.
It is also hugely frustrating and disappointing for the tournament and fans. Losing one of the favourites to injury is always a blow, but even more so when it's a home player.
But although it's a sad end to the year for Murray, we must not forget what a fantastic season he has had. His performances in the Grand Slams were so consistent - a final and three semi-finals - and at and Shanghai he added two more Masters 1000 titles to his collection.
He now has a well-earned break and it's important he recovers totally from the groin problem. You don't want something like that to carry on niggling and certainly not into 2012.
Your training block before the start of a new campaign is the most important of the year and with so much at stake, you have to get it right.
I can understand what Murray's going through. It's bad enough that you have to pull out of one of the biggest tournaments of the year, and in your own country, but on top of that you've got the responsibility of going and speaking to all the media - probably the last thing you want to do.
It is easy in hindsight to say he should have played fewer matches after the US Open, but you don't necessarily expect to win three tournaments in a row as he did.
And if you look at it in terms of the number of events he entered in that period - four - I don't think he played excessively. It's always something to be aware of, but on the whole he's done a very good job with his schedule.
You're always looking to make small adjustments and improvements if you can. For instance, a new diet is something he feels has made a big impact. He's just got to be aware of when he needs matches and when he needs rest.
Nor can you really blame the ATP, the governing body of men's tennis, for injuries. Ideally the schedule would be a few weeks shorter but it's difficult to please everybody.
From the players' point of view, though, this emphasises the need to have an independent body representing them.
The ATP is 50% players, 50% tournaments and that causes a conflict of interest because the players will say "we want a shorter season" but the tournaments will say "hang on, if you get rid of my tournament I lose my job". It's another reason why that structure should be looked at.
This is certainly a golden generation in men's tennis, however, and looking ahead to 2012 things couldn't be more exciting.
You've got Novak Djokovic trying to emulate what he has done this year, which will be very, very difficult. Rafael Nadal will be trying to get back to winning ways in big tournaments and hold on to his French Open title, while Roger Federer is eager to add to his Grand Slam haul and right the wrongs of Wimbledon and US Open.
And, of course, Murray is trying to get that elusive first Slam under his belt. It couldn't really be better poised.
If I could improve Murray in one area, it would just be his mental focus when things aren't going perfectly - dealing with adversity, controlling his frustration, cutting down the dialogue with his player box. That's when he struggles most.
It gets him distracted and stops him from being able to play his best tennis.
But, as I've always said, he has a Grand Slam title in him - and he's got four more brilliant opportunities next year.