Wawrinka has enjoyed the best year of his career and victory in his maiden appearance in the prestigious season-ending event at London's O2 Arena was another feather in his cap.

The 28-year-old, who hit 43 winners to 30 by Berdych, showed his class and composure after being blown away in the second set tie-break, recovering to win the opening match of the tournament in two hours and 25 minutes.

Seventh seed Wawrinka will play world number one Rafael Nadal and Spain's David Ferrer in his remaining Group A matches later this week.

After spending most of his career in the long shadow cast by his more successful compatriot Roger Federer, Wawrinka is clearly relishing his moment in the spotlight.

He will finish the campaign ranked in the world's top 10 for the first time and his hard-fought win over Berdych continued a trend that started at the Australian Open in January when he pushed Novak Djokovic to five sets before losing an epic fourth round clash.

The Swiss then reached the French Open quarter-finals, but the high point of his year came at the US Open when he defeated Berdych and Wimbledon champion Andy Murray en route to the semifinals.

Few other tournaments on the ATP Tour can match the cacophony of pop music and laser lights that greet the players when they walk on court at this event, but Wawrinka showed no signs of being distracted as he held serve to love in the opening game.

That set the stage for Wawrinka to take the attack to Berdych on the big Czech's serve.

Wawrinka kept the pressure on the 2010 Wimbledon runner-up with some accurate ground-strokes and earned his reward when the Czech double faulted and then missed a forehand down the line to give his opponent a 4-2 lead.

The 28-year-old had won seven of his previous 12 meetings with Berdych, including the last two, and he had the upper hand again as he closed out the first set on his fifth set point.

Berdych gradually upped his game and when it came to the second set tie-break he really turned on the style, taking all seven points to level the match.

However, Wawrinka had the perfect response as he broke for a 3-1 lead in the final set before sealing a victory that made him the seventh player to achieve 50 match wins on the ATP Tour this season.