Andy Murray wins but suffers surface tension

Andy Murray was heavily critical of the state of the courts at the Madrid Open after beating Tommy Robredo in straight sets.

The Scotsman reached the quarter-finals with a 7-5, 6-1 win in one hour and 43 minutes in one of his best results on clay.

But Murray, who is 22 tomorrow, admitted afterwards that conditions at the new court had contributed to his laboured first set effort.

Murray is the defending champion in the Spanish capital but the change in surfaces from hard court to clay for this year's event has brought with it a few teething problems.

He said: "Normally on clay when the ball hits the line it shoots through but here the lines are sitting quite high so it's bouncing off to the sides, especially so when the court gets dry because it's still not that hard. At the back of the court there are some bad bounces.

"But I'm sure it will get better as the tournament goes on and I'm sure it'll be better next year."

The Scot admitted his win against clay court specialist Robredo had given him great satisfaction, although he conceded the windy conditions had made for a scrappy contest.

He added: "Robredo is a top-10 clay-court player.

"He's been to the second week of the French Open quite a few times and has won tournaments on clay.

"The win was good but the conditions were very tricky, the court at the end of the first set was really dry and it was really difficult to move. I was a little bit tense early on but felt better in the second."