Federer grabs No 1 priority

Victory for del Potro means all four players in Group A can progress to the knockout stage in the ATP World Tour finals.

Roger Federer ended 2008 defeated, deflated and dethroned, but, 12 months on, and having beaten Andy Murray 3-6, 6-3, 6-1 at the ATP World Tour finals in London, he is guaranteed to end 2009 as world No 1. Murray was the first player to inflict defeat on the 28-year-old Swiss this year, beating him in the semi-finals of the Capitala World Tennis Championships in Abu Dhabi in January. Federer, however, insisted finishing the season as the top-ranked player was more important than his second successive Group A victory at the O2 Arena on Tuesday night.

"Obviously, that was one of my big goals for this season. And it's one of the greatest performances," he said. "Playing so well at the most important moments, it's been the key this year. "I think it's a wonderful achievement. It's official. It's a wonderful feeling [and] I think this is more the time to celebrate No 1 than celebrate the victory over Andy." It will be the fifth time the father of twins has finished the year as world No 1.

Federer now faces Juan Martin del Potro in his final match of the round-robin group stage tonight with his place in the last four not yet confirmed. Del Potro's victory over Fernando Verdasco on Tuesday results in all four players in Group A still able to progress. The Argentine scraped past Verdasco 6-4, 3-6, 7-6 and will progress to the last four with victory over Federer, whom he defeated in the final of the US Open in September to claim his maiden Grand Slam.

"I served much better," said del Potro, who lost to Murray in his opening Group A match. "I was focused in the important moments and I took my opportunities." Murray faces Verdasco this afternoon with the winner likely to book a place in the semi-finals. "I just have to win against Verdasco," said the Scot. "I think that's pretty much what I have to do." In Group B, defending champion Novak Dokovic lost in straight sets to Robin Soderling last night.

The Swede clinched a tight first set 7-5 on a tie-break then took complete control to cruise to victory, taking the second and decisive set 6-1. Afterwards, Soderling said: "I feel pretty good right now. I played a great match." @Email:gmeenaghan@thenational.ae

Updated: November 26, 2009, 12:00 AM