But how much do we love him? That is the question as Andy Murray takes on Andy Roddick in the semi-finals at Wimbledon this afternoon. We have seen a very great deal to admire in Murray, rather less that commands easy affection. It is at times such as this that we must look at the confusing, complex and often contradictory aspects of our - necessarily one-way - relationships with our sporting heroes.

Murray is hard to love right now. That doesn't make him unloveable, even in the public sense of the term. It just means that it's hard work; work not everybody is prepared to put in. Because Murray doesn't go out of his way to make it easy. He doesn't do charm. He shows no sign of even wanting to be loved.

Oh, he loves surfing the wave of partisan support on Centre Court, but that's different. After a slightly uneasy start in his first-round match against Robert Kendrick, he got used to Wimbledon and its ways once again and he used the crowd shamelessly in his famous five-set victory over Stanislas Wawrinka on Monday night. It's easy to cheer for Murray, less easy to find softer feelings for him.

Not a criticism, an observation on his method: Murray has put together a public persona in which he gives nothing away. It's a pose that suits his real nature. He wants to be aloof and untouchable. This is partly a defensive posture, partly an aggressive one. It's main aim, of course, is to help him to win tennis matches.

That means he never gets terribly pleased with himself. He doesn't express delight, or relief, or joy. He doesn't give us much to share apart from victory, and in some ways that's not enough. But Murray knows that the man who celebrates winning the semi-final too much is the man who loses the final. Murray is filled with the most lofty ambitions and is concentrated upon them. Winning our hearts is a pretty low priority.

It doesn't help that he carries the handicap of his teenage years. We are always slow to change our minds about the nature of a public personality, even if the person in question goes to the trouble of growing up or otherwise changing. That soupçon of Kevin has long since been obliterated from his life, but we haven't forgotten it.

The truth is that Murray's rather self-conscious maturity - well, he's 22, anyway - is also a little off-putting. He has created for himself a honed, primed-for-victory body and is working hard on a ditto mind. He had good material to work on in both cases, it must be said.

So when Murray makes his public appearances, he is always rejecting his public in some way. He is not rude to his interviewers, not obstructive, not unpleasant, he is just working to a different agenda. He is thinking about winning tennis matches, he is not interested in how it feels. In the politest way possible, Murray can't hide the fact that he'd really rather not talk to us.

Some highly successful British athletes inspired instant and lasting affection, people such as David Beckham and Andrew Flintoff - and it is in their company that we must think of Murray, if he wins his next two matches. Flintoff's easy, unassumed good-fellowship is highly likeable - but then Flintoff loves to be liked. He said that he would only ever be captain by remaining “one of the lads”. He couldn't bear the idea of being unpopular.

And then there is weakness. Flintoff's weakness gives him a vulnerability; is it possible to love anybody without vulnerabilities? The drinking scrapes, the contrition; the triumph, the wholehearted effort, the relish for competition - all these things make Flintoff vastly popular. He was cheered to the echo again this week, despite failing with the bat and admitting yet another daft cock-up.

Beckham has invented a new kind of public love. He is a man whose need for public love is pathological. His wife said that he boasts about being more of a gay icon than she is ... the sort of story that brings out a weary smile of affection in most of us. You can think what you like about Beckham, but no one can say that he isn't loved.

But we don't always love our champions. Sometimes, even if they have shown us their vulnerabilities and given us a few hints about the complexities of their characters, we can find them unloveable.

Lewis Hamilton, for example. We were happy to cheer for him, but we didn't take him to our bosoms. We didn't make him BBC Sports Personality of the Year, even though he was - and still is - world champion.

It's not because of race: everybody adored Frank Bruno. Partly, it was the too-swift decision to move to Switzerland and swerve the taxes. Partly there was his association with the scandals of the McLaren Mercedes Formula One team. But mainly, I think, it was the feeling that Hamilton was overproduced. A bit too groomed. Trying a bit too hard to be Tiger Woods - and who wants anybody to be Tiger Woods, for God's sake? I mean, jolly good at golf, but a master of corporate gobbledegook and look at me, aren't I a wonderful role model, make sure you give the cheque to my agent.

Hamilton was just a bit too calculated, you see, and we can see through that and we don't like it. So while we admire his skills and will cheer if he gets a car that can move out of second gear, we won't go overboard with love just yet. We are ever so slightly careful when it comes to love.

There is a sense in which Murray doesn't represent us. That is probably true even if you are Scottish. Murray is playing an individual sport and is, quite rightly, using every scrap of his energy to try to win this tournament. He has no time for anything outside this. No interest. He is centred on himself. And if you don't like that, you can get stuffed.

And me, I happen to like it very much. I can see what he is doing, I can see the way it is working for him. His concentration on this one aim is admirable. It doesn't make you want to hug him, or buy him a beer, or listen to his jokes, but it's something effective and admirable.

Murray has tried to turn himself into a machine for victory. He has worked frighteningly hard to eliminate the weaknesses in his game, in his physique, in his mind. He has done his best to conceal the vulnerabilities that might create a spark of affection. He really is only and always thinking about winning.

That makes him a rather intimidating person. You'd walk rather stiff-legged around him, even if you had no idea who he was. He gives out that sense of elected loneliness, that self-isolation that you find in some champions. It follows, then, that he needs victory to complete his personality.

That raises the stakes really rather high. He needs a victory, if not here and now, then big and soon and gland-slam, to be himself - to become, at last, Andy Murray. And perhaps then, he'll let us in. Though I wouldn't count on it.