Andy Murray confessed on Wednesday that it is a complete "surprise" for him to be in the French Open semi-finals, because he does not believe he has played well all week.

25307 - Murray not happy with French Open form

Murray set up a semi-final showdown with Rafael Nadal by beating Juan Ignacio Chela in three sets in Paris. Friday's encounter will be the Brit's first semi-final at Roland Garros.

Injury problems, changing weather conditions and two-day matches caused by fading light have all tested Murray's resolve, and while he is happy to be in the last four, he admits his form has not been perfect.

"I'm surprised I'm here, to be honest, because I haven't actually played that well," said Murray. "Aside from everything else that's happened, I haven't played particularly well.

"That's a very good sign for me because a few months ago I was not playing well and losing badly. I haven't been playing that well. I'm in the semis of a slam. That's a good sign.

"Glad that I'm here, but I've got two days to rest up, recover, and get ready for Rafa, which is always one of the most exciting matches for me on the tour."

Murray is currently playing with a damaged ankle, but he sees that having no influence over his semi-final encounter.

"It's definitely getting better, with each day and more sort of playing a match on it. You gain confidence more with the movement each time.

"I still, at times, wasn't moving great. I was moving a lot better forward today. Sideways could still definitely be better. But I felt it a few times. Nothing major, but I just need to, in the next couple of days, do all the right things again. A lot of treatment, a lot of icing, and I'm sure it will get better.

"I think in the buildup to the French I was playing very well, and now I'm going to have to get that level out on Friday and sustain it for a long period to beat Rafa.

"But I feel I can do it. It's just making sure that come Friday I play my best tennis. I have to play a very consistent match, and I have to be mentally strong. Tactically I'm going to have to be very good.

"So I can definitely win. I just need to play my best."