First time a charm for Wawrinka

A week ago, after a dozen years as a professional, Stanislas Wawrinka finally locked down his first-ever spot in the year-end tournament. On Monday he didn't exactly behave like a star-struck newbie.

After getting shut out in a second-set tiebreaker, the 28-year-old Swiss player came back and defeated Tomas Berdych 6-3, 6-7 (0), 6-3 to win his first career match at the Barclays ATP World Tour finals. Technically, it was an upset because Wawrinka is seeded lower than Berdych (No. 7 versus No. 5), but it was his third straight win over Berdych and sixth in seven matches.

"I play him three times, I beat him three times," Wawrinka said afterward. "Three important ones. First in Madrid to come back into the top 10, then US Open to make my first [major] semifinal and then here.

"I'm really happy the way I'm playing against him, but it doesn't mean I'm a better tennis player than him."

It was his 50th match win of the season, another career best.

Although his improved forehand has been a factor in his rise in the rankings -- the past five years he has finished between No. 13 and No. 21 -- it is Wawrinka's newfound calm under duress that has been the biggest difference.

Looking for some proof? Wawrinka saved all five break points he faced and took two of four on Berdych's serve.

"In general, I think I'm dealing much better the pressure," Wawrinka said. "Even when I'm nervous, you don't see it. I keep my level. I keep my intention on what I want to do."

Berdych lost his opening match at the year-end championships for the fourth consecutive year.

"Losing is not a good start," said Berdych. "But there are still two other matches to go. It was a very close game again. Stan was better in actually like executing the chances."

Off-beat statistic of the day: The middle-set tiebreaker was the first bagel in five years at this event, when Nikolay Davydenko did it to Jo-Wilfried Tsonga in a decisive third set during round-robin play.

Del Potro stays hot

Richard Gasquet won the massive -- 32-stroke -- first-point battle against Juan Martin del Potro, but ultimately lost the war.

Del Potro, at 25, the youngest player in the field, beat Gasquet 6-7 (4), 6-3, 7-5. It was his sixth win over Gasquet in seven career matches. Gasquet, the No. 8 seed, is appearing at the year-end championships for the first time since 2007. The lively match went 2 hours, 23 minutes.

While Novak Djokovic comes in with a 17-match winning streak, the Argentine has been hot, too, winning 16 of 18 matches since the US Open and two titles.

Verdasco returns

The last (and only) time Fernando Verdasco played at the season-end championships, he went 0-for-3 in round-robin play. That was four years ago.

Monday, he and partner David Marrero defeated London's defending doubles champions, Marcel Granollers and Marc Lopez, 6-1, 6-4. Marrero and Verdasco, who were playing their 34th match of the year, are 7-0 against their fellow Spaniards.

The No. 8-seeded team of Mariusz Frystenburg and Marcin Matkowski defeated the No. 5 team of Aisam-Ul-Haq Qureshi and Jean-Julien Rojer 6-3, 7-6 (8).

The No. 1-seeded team of Bob and Mike Bryan faces No. 3 seeds Ivan Dodig and Marcelo Melo in Tuesday's first night match.

Standings, through Day 1

Note: Players in each group will meet once each to determine the four semifinalists.

Group A
(7) Stanislas Wawrinka 1-0
(1) Rafael Nadal 0-0
(3) David Ferrer 0-0
(5) Tomas Berych 0-1

Group B
(4) Juan Martin del Potro 1-0
(2) Novak Djokovic 0-0
(6) Roger Federer 0-0
(8) Richard Gasquet 0-1

Forward spin: Day 2

They're getting right to the point in London, no fooling around.

The card at the Barclays is precisely the same one presented three days ago at the Paris Masters semifinals. In the afternoon match, No. 1 Rafael Nadal meets No. 3 David Ferrer, who ended an 0-9 run against Rafa with a surprisingly emphatic 6-3, 7-5 win in Paris. Ferrer went on to lose to Novak Djokovic in the final.

Nadal needs to win two matches in London to clinch the year-end No. 1 ranking.

Tuesday's final evening match pits the No. 2-seeded Djokovic against No. 6 Roger Federer. In Paris, Djokovic came back to win 4-6, 6-3, 6-2 after being down a set and a break against Federer. Certainly, the Swiss champion will have an edge in experience. The six-time year-end winner has a 42-9 record at the event; Djokovic's career mark is 14-9.