Paris, Nov 3: Second seed Novak Djokovic of Serbia defeated Marin Cilic of Croatia 4-6, 6-2, 6-3 in quarter-finals of the Paris Masters tennis tournament at the Bercy Arena here on Friday to set up a semi-finals class against Roger Federer.
Djokovic came back from a set down to beat the Croat in two hours and 12 minutes.
The 32-year-old Serb revealed after the match that he had been struggling with some form of illness.
'I'm still struggling. It's kind of a flu. But it's not easy to perform every single day, the energy levels are not as high. And, try to manage the situation, but I've had this particular case before so I hope I can progress day by day,' the tournament's official website quoted him as saying.
Now, he will face record 20-time Grand Slam winner Switzerland's Federer on Saturday.
In another men's singles match, Federer defeated Kei Nishikori 6-4, 6-4, his sixth straight win against the Japanese player.
The Swiss has won this tournament only once, way back in 2011. He has been playing in Paris Masters after three years.
Federer and Djokovic have faced each other 47 times.
The Wimbledon and US Open champion Djokovic had beaten Federer in their past three meetings and leads over him 24-22.
Federer is one shot of his 100th title wins in his career.
Last month, he sealed his 99th tournament victory by defeating Marius Copil 7-6, (7-5), 6-4 in the ninth Swiss Indoors title.