Andy Murray against Rafael Nadal at Wimbledon - it doesn't get much more exciting than that.
With the crowd passionately behind Murray, which they seem to now be, it will be a fantastic match.
There are, of course, ifs and buts and the key thing could be how well Murray recovers from his epic five-set fourth round against Richard Gasquet.
To be honest, I don't know whether he will be able to recover to be fitter than Nadal.
When Murray was slugging away, Nadal was already home with his feet up.
He's the fittest man in tennis and if you walk on the court feeling a little bit off then you'll have no chance.
But Murray has a good game, he can attack and if he can perform like he did against Gasquet, particularly in the last two sets, he's got a real chance.
The key will be Andy's serve. The serve was brilliant against Gasquet as was his attacking play - he really out-hit the Frenchman.
Murray was being thumped for virtually all of the first three sets but was somehow able to hang in and win the match. A fantastic victory.
That was the match we've been waiting for all tournament, it was a real five-set thriller that has set the championships alight.
It was a great match-up, with Murray and Gasquet proving themselves to be two brilliant players.
It was a perfect and a perfect match. You have to congratulate both players - they both played their part.
Gasquet was a great loser - he was very respectful towards the crowd and his opponent - and Murray was the player everyone wanted to win for the good of the tournament.
Fortunately for Great Britain, he obliged.
Pat Cash and Michael Stich were speaking on BBC Radio 5 Live.