Andy Murray opened his Valencia Open challenge with a 6-3, 6-3 win over Jurgen Melzer, but his performance failed to inspire in the Spanish city.

In a match littered with poor serves and unforced errors, the third seed - who won the title here in 2009 - just about held the edge to progress through to a second-round tie with Italy's Fabio Fognini.

Murray is playing in his fifth consecutive tournament, having won in Austria last week, and is looking to secure his place at the ATP World Tour Finals next month.

But he will have to improve significantly if he is to better the result of David Ferrer, who is the top seed in Spain and aiming to bump the Scot from eighth place in the race for London.

"The court is slower than in Vienna," said Murray.

"It took me some time to adapt but after a couple of games, I went up a level."

Having begun the week eighth in the Race - and in line for a place in next month's eight-man event at London's O2 - Murray's hopes received another boost when Tomas Berdych was surprisingly beaten 6-3, 6-2 in round one by Pablo Andujar.

Berdych, who won the title in Stockholm on Sunday, is in seventh place, 220 points above Murray, but his defeat means the Scot would go all the way up to fifth if he were to emulate his 2009 title-run.

Roger Federer and Rafael Nadal enjoyed straightforward outings at the ATP Swiss Indoors - progressing with minimal fuss in Basel.

Top seed Federer took just 46 minutes to beat Gilles Muller 6-2, 6-1, while Nadal cruised to a 6-1, 6-1, second-round success over Pierre-Hugues Herbert.

French Open finalist Simona Halep stunned Serena Williams 6-0, 6-2 at the WTA Finals in Singapore.

She had lost in her three previous encounters with the current world No.1 and had never beaten a top-three player before.

However, Halep played what she described as "the best match of my life" to hand Williams the joint heaviest defeat of her career.

"It's the first time I've beaten Serena. It was a dream to beat one of the (Williams) sisters because they are very good players," said Halep also referring to Venus.

Williams said: "Embarrassing I think describes the way I played. I've seen her play a lot. Like I said, she's never played like this before."