By Piers Newbery BBC Sport at Wimbledon

Del Potro was the youngest top-100 player at the end of 2006

How's your luck? You head to Roland Garros for your first French Open and draw Rafael Nadal in the first round, then you move on to your first Wimbledon and get Roger Federer in round two.

When you're 18 years old and have many more chances ahead of you it probably softens the blow.

Argentina's Juan Martin del Potro is proof that the tennis world never stands still, leading as he does the next generation beyond Nadal, Andy Murray and Novak Djokovic.

Already up to 56 in the world and with the type of hard-hitting game required to make the grade these days, Del Potro put up as good a fight as anyone, bar Federer, against Nadal in Paris.

And now the 6ft 5in right-hander must face the other seemingly impossible mission in tennis when he plays the four-time champion in round two at what he calls "the cathedral of tennis."

"I think I have to play my match and forget the people, and the person I have in front of me, and try to do my best," Del Potro tells BBC Sport.

I'll try to do my best to win, but he has maybe 80% more chance than me Juan Martin del Potro

"I have to play relaxed. I don't have anything to lose, that's the point, no?

"All matches are experience for me - especially against Nadal or Federer. I'm going to have many things to learn for my future and I'll try to do my best to win, but he has maybe 80% more chance than me.

"I have a little chance but I will try to take it. I want to beat him and I'll do everything I can."

Well, a 20% chance is probably more than most onlookers would give Del Potro on Wednesday, and it's certainly more than most players give themselves against the world number one.

But despite his age Del Potro clearly sees this latest test as another staging post towards the stellar career widely predicted for him.

"Wimbledon is the biggest tournament in the world, I think it's the best one," he says.

"Two years ago I was dreaming about playing Federer in the main court of a Grand Slam and on Wednesday I have the possibility."

And one thing Del Potro has in common with all bright young things racing up the rankings is that, from the time he won the unofficial junior world title at the Orange Bowl in 2002, he has been used to winning matches.

So if he were forced to choose an opponent, who would it be - Nadal in Paris or Federer at Wimbledon?

"I think it's the same because Nadal is the king of clay courts and Roger is the teacher on grass," says the teenager.