Former tennis player Tim Henman?believes that?Roger Federer?and?Rafael Nadal?will be tough to conquer at Wimbledon. The Swiss player will face Kevin Anderson in the quarterfinals. Meanwhile, Nadal will face Juan Martin del Potro.

With regard to the world no. 2, Henman said: ‘He looked so solid, he was so solid coming through the first week and he?s continued that in the fourth round beating (Adrian) Mannarino in straight sets. You look at the top two, Federer and Nadal, it really is going to take something extraordinary to beat them.

When I say extraordinary, it?s going to be someone like (John) Isner, (Milos) Raonic or (Kevin) Anderson, who just serve 40, 50, 60 aces to beat them. I just don?t see them losing to a conventional player. Someone that obviously plays well, good serve, solid from the back of the court, that?s just not going to get it done.

I think their level is just so high that it will take one of them almost freak players to beat them. Otherwise, we?re going to be in a repeat of the 2008 final when Federer played Rafael Nadal.’

Henman added: ‘Everybody is different and he [Nadal] is strong and very intense.

He really likes to get his footwork going early on and that is to get rid of the nervous tension. He wants to get his feet working early and then be aggressive with his shots. Federer is at the opposite end of the spectrum and looks like it his first practice session of the day when he comes on to court.

He has to probably be a little bit more offensive and that is to do with his court position. On clay, he can stay beyond the baseline but grass is one of the toughest surfaces.’

Federer is currently hunting for his 9th Wimbledon title and Nadal will be hoping to deny him.