Novak Djokovic, Stan Wawrinka
Wawrinka had beaten Djokovic at the Australian Open earlier this year.Reuters file

Novak Djokovic and Stan Wawrinka will renew their rivalry once more on Day 4 of the ATP World Tour Finals at the O2 Arena in London on Wednesday.

Both players had won their opening matches in Group A, with Djokovic beating 2014 US Open champion Marin Cilic of Croatia 6-1, 6-1, while Wawrinka saw off Tomas Berdych of Czech Republic by the same scoreline.

Djokovic, the world no.1 and defending Tour Finals champion, is looking to be the first player since Ivan Lendl (1985-87) to win three consecutive World Tour Finals. Coming off the back of a successful title defence at the Paris Masters, the Serbian was happy with his clinical performance against Cilic.

"Of course, winning in straight sets helps a lot for the rest of the tournament. But I'm going to try to win every match I play, obviously. But it does help for, you know, qualifications for the semifinals eventually and so forth. Hope I can just continue playing this well," the 27-year-old pointed out.

Wawrinka, on the other hand, found his big break this season, winning the Australian Open title earlier in the year - his first singles major - beating Rafael Nadal in the final. The Swiss has struggled a little of late and was knocked out in both Basel and Paris but with the win over Berdych on Day 2, he has set himself up for the tournament.

"I didn't expect to win that easy. But I was ready to play well. I had a great week of preparation," the no.4 seed stated, adding: "When I feel good on the court, I'm ready to beat everybody. It's never easy, but you have to fight for it. Normally when you play the top‑10 guys, you are in the quarters or semifinals of a tournament. So the confidence is there. I'm feeling great mentally."

Djokovic leads the head-to-head series between the two 15-3 but Wawrinka won their only meeting this year, at the Australian Open.

Where to Watch Djokovic vs Stan Wawrinka Live

Djokovic vs Stan Wawrinka will not start before 1.30am IST (7pm GMT), with Ten Sports and Ten HD providing live coverage in India, while the match can also be watched via live streaming online on Ten Sports Live.

Viewers in the UK can watch the match live on Sky Sports 3 and Sky Sports 3 HD, while they can also catch the action live on Sky Go.US viewers can watch the game live on Tennis Channel on TV or online on HERE.

Berdych and Cilic will take on each other in the other match in Group B.

Both men had lost their first match, and today's encounter will be a matter of survival for them. The winner can harbour hopes of qualifying to the next round, while the loser will crash out of the competition.

Where to Watch Berdych vs Cilic Live

Berdych vs Cilic will not start before 7.30 IST (2pm GMT), with Ten Sports and Ten HD providing live coverage in India, while the match can also be watched via live streaming online on Ten Sports Live.

Viewers in the UK can watch the match live on BBC Two, Sky Sports 3 and Sky Sports 3 HD, while they can also catch the action live on on BBC iPlayer or Sky Go.US viewers can watch the game live on Tennis Channel on TV or online on HERE.