It's the main reason I went for a DSLR. Tennis, I mean. I've been in love with the sport since...forever, really, though not so much as a player. I did play when I was a kid but I was - still am - too lazy, basically and I hate to sweat. The only two sports I ever got actively into are swimming and horse-riding. You can't sweat in the water and horses do most of the hard work (actually, horse-riding can be really tiring BUT being with a wonderful animal as a horse makes it all worth it).

So, anyway, I love tennis as a spectator. And most of all I love to take pictures of tennis players. It can be an extremely photogenic sport and, being played outdoor and in daylight most of the time, you don't need an insanely fast lens to get decent results. Getting decent results, in my opinion, isn't hard: groundstrokes can be very predictable and once you've observed a player for a few minutes, you should generally be able to catch nice forehands and backhands with the ball well in the frame almost everytime. Providing you set a fast enough shutter speed (1/800 is the absolute minimum I try to keep it at 1/1250 or more, depending of the light), things will look nice.

Getting great results, on the other hand, is a whole another deal. First of all, your equipment starts to matter. Fast autofocus, large apertures, high fps capability, all of these things will make the difference when you're trying to capture that unpredictable moment or maybe some netplay action. And then there's the skill of the photographer and the sensibility to catch that special moment, not necessarily one of action.

I'm in the first bracket: decent results with the predictable moments. I've realized that I'm noticing the limitations of my current budget telezoom more and more and I think that's a good thing. It should mean I'm getting better. Hopefully :)