Rafael Nadal progressed through to the Madrid Open quarter-finals today, and he was supported by none other than Cristiano Ronaldo.

The Real Madrid superstar took time out of his busy schedule to be in the crowd - pictured above - as the world no.1 stormed past Jarkko Nieminen.

Ronaldo is preparing for one of the closest La Liga title run-ins in recent times with his club, a Champions League final against city rivals Atletico also in the offing.

The man who is still officially the world's most expensive footballer at £80 million - Gareth Bale's fee is expected higher, but there is no proof - limped out of his side's disappointing 1-1 draw with Valladolid, but was fit enough to watch the tennis.

The 29-year-old, with his young son, were among a number of other Spanish celebrities who took their place in the 'Magic Box'. 

They would have been pleased with what they saw as Nadal breezed his way past the Finnish opponent with a 6-1 6-4 win. 

It has not been plain sailing for the 26-year-old at recent events. He is bidding for a fourth Madrid Open title this week as the French Open looms later this month, but preparation has been far from ideal.

He is supposedly the 'King of Clay', but quarter-final losses at the Monte Carlo Masters and Barcelona Open, on his favoured surface at both, against compatriots David Ferrer and Nicolas Almagro, respectively, have raised doubts over his form.

Victory here in Madrid, and a good showing at the Rome Masters which begins next week, will go some way to silence the critics.

Nadal will hope to have ironed out the imperfections in his game in time to launch an assault for a ninth title at Roland Garros.

Only once has he lost on the French dirt - back in 2009 - and another title would draw him level with Pete Sampras as joint-second on the all-time Grand Slam singles title win list. The American has 13 to his name, and that has only been bettered by Roger Federer.

Federer was expected to challenge Nadal in Madrid but he was forced to pull-out without playing a game after his wife Mirka gave birth to the couples' second set of twins. 

The Spaniard's hopes have been boosted further in his home capital after Andy Murray was subjected to a shock defeat by Santiago Giraldo. Also, Novak Djokovic's withdrawal through injury meant that Nadal's world no.1 ranking is safe. It had been on-the-line heading into the Masters 1000 event.

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