Serbia's Novak Djokovic will square off Monday against arch-rival Rafael Nadal in the championship match of the Barclays ATP World Tour Finals after cruising to a 6-3, 6-3 victory over Stanislas Wawrinka.

The defending champion needed only a workman-like effort in Sunday's second semifinal at London's O2 Arena, relying more on Wawrinka's errors than his own spectacular shot-making.

The only drama came when the Swiss took an early 2-1 first-set lead with a service break, but the world No. 2 quickly turned things around to reel off five of the next six games and the outcome was never in doubt after that.

"I had the feeling that I was playing good, hitting well the ball," Wawrinka was quoted as saying on the ATP World Tour's Web site.

"But I think I didn't have enough energy today. I think I was little bit late physically. Against him, that makes a big difference. I'm disappointed with myself because I had the feeling that could have done something better."

Djokovic comes into Monday's final on a 21-match winning streak, with his last loss being a four-set defeat against Nadal in the U.S. Open final.

The top-ranked Spaniard, meanwhile, is looking to cap off an outstanding year - in which he captured his eighth French Open title and second U.S. Open crown and regained the No. 1 ranking - by winning the biggest tournament to elude him in his career.

Nadal, who topped six-time champion Roger Federer in Sunday's first semifinal 7-5, 6-3, will try to become the third Spaniard to win the year-end championship event after Alex Corretja in 1998 and Manuel Orantes in 1976.

It will be Nadal's second championship match at the ATP Tour Finals, an indoor hard-court event where he has struggled to defeat his top rivals.

Djokovic won this event in 2008 and 2012. EFE