Tomas Berdych kept his hopes alive – however slim – at the Barclays ATP World Tour Finals on Wednesday with a straight sets victory over Marin Cilic.

Following a terrible start to his fifth appearance at the year-end championships, where he lost to Australian Open champion Stan Wawrinka 6-1, 6-1, Berdych rebounded with a sharper showing against another Grand Slam champion in Cilic. The Czech No. 1 defeated his Croatian opponent 6-3, 6-1 in a contest that lasted 75 minutes in total – one of the longest matches of the tournament so far.

“I felt much better on the court,” said Berdych. “But still it was not one of my best. That’s fair to say. But I think that’s the beauty of this event. One day you can be swept out from the court like I did and in two days’ time you can come up and you can play a different tennis.

According to ATPWorldTour.com, Berdych is 5-0 in his second round robin matches in London, as he has never lost that encounter throughout his five appearances at the event. He maintained that streak this year with his win against the reigning US Open champion.

Berdych took advantage of a slow start from Cilic to break for an early lead – one which he would not give up until he won the set 6-3. He would break twice more in the second set, in the fourth and sixth games to hand CIlic another tough loss.

The Czech’s win extends the straight sets streak at the World Tour Finals to seven consecutive matches, as none of the round robin matches played have shown even a spark of competitiveness.

Berdych will next meet world No. 1 Novak Djokovic, who recently defeated him 6-0, 6-2 in the final of the China Open.