Roger Federer, the world number-one, is to work with clay court coach Jose Higueras as he prepares for the French Open.

Federer has not had a coach since 2007 but has decided to prepare for the clay-court competition with Higueras at the Estoril Open in Portugal this week.

"He's one of the world's most respected and accomplished coaches. We are going to see if we could make a good team," said the Swiss player.

The 26-year-old has struggled for form so far this season and needs to win the French Open in order to complete a career Grand Slam.

In the last two finals at the Rolland Garros, Federer has lost out to Spaniard Rafael Nadal.

Higueras has previously coached Pete Sampras, Jim Courier, Michael Chang and Robby Ginepri.

In other news, Andy Murray has risen up one place in the world rankings. The Scot is now in 21st place although he will miss out of this week's Valencia Open due to a virus.

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