Nadal seeking lucky seven on Barcelona clay Spaniard shows no signs of knee problems

Home hero Rafael Nadal will try for lucky seven as the ATP Barcelona Open begins on Monday, with the Spanish king of clay already a champion in six of the last seven editions.

Nadal showed no sign of knee problems amid his storming return to tennis this week at the Monte Carlo Masters and will be hoping to keep up his trademark momentum on his favourite surface as he performs for the Catalan crowds expected to pack the Real Club de Tenis.

Nadal's domination of the event has been near-total with his only slip-up coming in 2010, when he had to rest his fragile knees.

The Spaniard will take to the court after the bye awarded to the first eight seeds and after receiving the highest praise from legend Bjorn Borg, who called him the best-ever on the surface.

"Let's wait when I finish my career," said the modest Nadal, "My uncle always told me that when Bjorn went on court, everybody felt he was unbeatable. So that probably means that he can be the best of the history.

"I don't feel unbeatable, but I have much better results that I ever dreamed. I don't know if I'm (the equal) of Bjorn."

Andy Murray, who learned his tennis as a Scottish teenager transplanted to the Catalan capital, will take the second seeding after being forced to withdraw last year to let a right elbow injury rest.

World number four Murray has made only three previous appearances at the event, winning one round from four matches. His last showing was 2009, when he lost to Mario Ancic.

Murray is hoping to go father than his 2011 semi-final at the French Open next month and good early results on clay are all a part of the plan.

The Scot lost a tight Monte Carlo quarter-final to Tomas Berdych, who also joins the Spanish field as fourth seed.

Spaniard David Ferrer, last year's losing finalist to Nadal, is seeded third as he tries to overcome a surprise opening loss in Monte Carlo.

Spaniards have a stranglehold on the tournament, having won 12 of the last 15 editions dating to 1997 when former Davis Cup captain Albert Costa lifted the trophy.