Novak Djokovic was able to describe what every player is bound to feel ahead of a match against Ivo Karlovic.
The world No1, who has dropped just six games in his first two matches of the year in Doha, has a quarter-final date with the tall Croatian serving machine on Thursday and he was quite forthcoming with regards to how he perceives his clash with Karlovic, the man of 9,041 aces.
"How do you think I feel about that?" Djokovic asked with a laugh. "I'm definitely going to try to get some good sleep so my reaction tomorrow is quick, because I'm going to need that, definitely. We all know how Ivo is serving. He is one of the best servers ever to play the game. He's right up there on the all-time list of aces."
Karlovic is No3 on the all-time list to be precise. Only Goran Ivanisevic (10,183) and Andy Roddick (9,074) have struck more aces in their career and Karlovic is determined to surpass them.
"It's my ambition to overtake Goran before I retire," said the 35-year-old Karlovic.
Djokovic was asked if he enjoyed facing someone like Karlovic. The Serb said: "Honestly, I'm still to meet the player that enjoys playing him. I don't think that anybody really enjoys it. It's a big challenge, obviously, mentally I think most of all.
"The key is to try to get as many returns back in play. Also there will probably be some games where he's going to serve two, three aces. I'm going to have to accept that, but, you know, these particular matches, when you play somebody that serves that well, one of the best all time servers in tennis history, then you just need to wait and be patient."