Knock him down and one thing is certain about Tomas Berdych at the ATP World Tour Finals – he will bounce right up again.

The 29-year-old Czech has qualified for the year-ending showpiece beside the River Thames five years in succession and each time he has lost his opening match.

On Monday he crashed 6-1 6-1 to Stanislas Wawrinka but, true to form, he rebounded to win his second group match at the 02 Arena yesterday, outclassing Marin Cilic 6-3 6-1.

Just as his opening match record is lamentable, albeit his tormentors have been Rafael Nadal, Novak Djokovic, Andy Murray and Wawrinka twice, his second match record now reads 5-0.

So, what transformed the world number seven from a pussycat to a tiger in the space of two days?

“I think that’s the beauty of this event,” he said after keeping alive his semi-final spot hopes with a top-two finish in Group A.

“One day you can be swept out from the court like I was and in two days’ time you can come up and play different tennis.

“Basically there were no miracles in that time in between the matches. I just had a good practice session yesterday, good rest, refocused again, and ready to go for another match.”

Berdych was certainly a far different proposition to the one that was thumped by Wawrinka.

He broke Cilic’s serve in the first game of the match and, after saving two break points at 4-3, never looked back.

Berdych said he faced “mission impossible” after his opening loss and while he is at least still in the mix, the odds are stacked against him with Djokovic his third opponent.

The last time they played, in the Beijing final a few weeks ago, Berdych managed two games.

Other result: Djokovic bt Waw-rinka 6-3 6-0.