• French Open

Nadal has a target on his back in Paris

Rafael Nadal is going to have to dig deep if he is to win the French Open © Getty Images

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You can never count Rafael Nadal out over five sets but this year's French Open is as open as it's been for a long time.

Whereas Nadal has always been the strong favourite going into Roland Garros, that's no longer the case. There are definitely some doubts going into this year's tournament, given the way Nadal's played over the last few weeks.

Murray faces pain in Paris

Andy Murray missed the French Open last year with a back injury © Getty Images

• Andy Murray has been handed a tough draw at the French Open with potential matches against Stanislas Wawrinka, Rafael Nadal and Novak Djokovic in the last three rounds.
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You've had four different guys winning the European clay events: Novak Djokvoic won the Rome Masters last weekend, Rafa won in Madrid, Kei Nishikori was victorious in Barcelona and Stanislas Wawrinka earned his first ever Masters series title in Monte Carlo.

Nadal perhaps also wouldn't have even had a European clay court title in the lead up to Paris this year if it wasn't for Nishikori withdrawing in the Madrid final after starting so well.

Everyone is surprised at Rafa's dip in form. He usually dominates the clay court season, but the other guys are stepping up against him.

Yes, he's making heavy work of some of them and he has got a relatively good draw but opponents have got a game plan when they step on court. They're being more aggressive and they're thriving with that 'nothing-to-lose' attitude, like Andy Murray did in their quarter-final in Rome when he took that first set 6-1.

The guys have now all figured out that this is the only way to play Nadal on clay. Can players maintain that level over five sets, though? That's the issue. Historically they haven't been able to do it.

I have an inkling it could be Djokovic's year. He's never won the French Open but on his day he's got the game that could beat Nadal.

Djokovic is only missing the French Open from his grand slam collection, so you can see the extra motivation he's going to have.

'The only threat to Serena is herself'

Don't bet against seeing a repeat of these celebrations at the end of the French Open © Getty Images

• You really have to wrack your brain to think of anyone who can stop Serena Williams from winning the French Open because the only person who can beat her is herself.
• If Serena has an injury, if she has a mental breakdown then maybe her name might not be etched on the trophy.
• But she's an incredible athlete, winning like she's winning and dominating the female game - she seems unstoppable.
• Victoria Azarenka has pulled out already, however Maria Sharapova is a potential threat. Ana Ivanovic has started playing a little bit better recently and she did beat Serena in three sets at the Australian Open.
• It's clutching at straws though, really, because there's no one out there who has the game or the weapons to beat Serena.

He's said he's basing his season around Roland Garros, which he did last year even though, ultimately, he didn't win it. You can see why it would be a priority for him if he believes that if he wants to be one of the greatest players of all time he's got to win all four majors, as Roger Federer and Nadal have done.

That wrist injury a few weeks ago in Monte Carlo helped him in some ways because he had a week off from Madrid and came back fresh for Rome.

It's fair to say that Federer was a bit distracted at that tournament after the birth of his third and fourth children. The interesting thing about Federer is that he's been playing better, he's been having a good year.

He's come back strong and he's definitely a contender. Rome was just a bit of a blip and he will definitely be in the mix with Nadal and Djokovic.

You can put Wawrinka in that mix now, too, but he is on what looks like the tougher half of the draw and ultimately I think he'll come up short in Paris. He can definitely win another grand slam but it's very unlikely that he will win two in one year.

This year I guess in many ways he's achieved his goals already with his first grand slam and first Masters win. His performances have been a bit up and down since the Australian Open, but he'll be there in the second week for sure.

Murray, in the same half as Wawrinka and Nadal, showed some form in Rome which we haven't seen for a while - he's knocking on the door as well.

It was a poor performance from Murray in Madrid against Santiago Giraldo but in Rome it was encouraging. Some of his tennis reminded us of what he did last year.

There are no points for Murray to defend at the French because he didn't play last year due to injury, but he will have a lot of points to defend in the tournament to follow after winning Queen's and Wimbledon.

Having a good French would ease the pressure a bit more going into defending those title in the grass court season, so Murray has every incentive to see how far he can go in Paris.

Chris Wilkinson is a former British No. 1, who now serves as a tennis commentator and as a coach for the LTA. He is ESPN.co.uk's resident expert, providing an exclusive view on the world of tennis.

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