Serena was always in command Thursday's photos

Serena Williams progressed into the third round of Wimbledon with a 6-4 6-4 victory over Belgium's Els Callens.

The top seed and defending champion had too much power for her opponent in a match which lasted just over an hour.

Williams will now face 28th seed Laura Granville after she overcame Ukrainian Tatiana Perebiynis.

The only glimmer of encouragement for Williams' rivals was the sight of her losing back-to-back service games in the second set.

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Callens battled back from 4-1 down to level at 4-4 courtesy of the double-break.

But an enraged Williams increased her efforts to secure the match-winning break.

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French Open champion Justine Henin-Hardenne breezed into the third round at Wimbledon with a 7-6 6-1 victory over Italy's Flavia Pennetta on Centre Court.

The Belgian, seeded three, was given a stiff test in the opening set by the hard-hitting 21-year-old Italian, who is ranked 55 and was playing at Wimbledon for the first time.

But Pennetta appeared to become demoralised after Henin saved a set point at 5-6 and then took the tie-break 7-2.

The Italian began to make mistakes and Henin-Hardenne raced through the second set in 23 minutes on a blustery Thursday afternoon.

Henin will now play Australian Alicia Molik, following her blitzing of Russian 31st seed Elena Likhovtseva.

Two-times Grand Slam champion Mary Pierce defeated 14th seed Eleni Daniilidou in straight sets.

France's Pierce produced a near-faultless display of power hitting to knock out her highly-respected Greek opponent 6-4 6-1.

The 1995 Australian Open and 2000 French Open champion has been plagued by injuries in recent years.

Pierce is unseeded at Wimbledon

But this win booked her a place in the third round at a major event for the first time since last year's Wimbledon.

Eighth seed Jennifer Capriati continued her good form by outclassing Swiss Marie-Gaianeh Mikaelian 6-2 6-1.

The American put on a tennis clinic on court number two - the "Graveyard of Champions".

"I haven't played out there in a long time. It was a little bit windy, but I was able to concentrate the whole match," said Capriati.

"The only thing I would dread was if it was a noisy court with lots of people walking around.

"But this is a nice atmosphere, that court. It's cozy. It's not so big.

Tenth-seeded Anastasia Myskina also only lost five games as she beat fellow Russian Lina Krasnoroutskaya.

Myskina won 6-1 6-4 without ever needing to slip into top gear against an error-prone opponent.

Krasnoroutskaya, a former world junior champion who missed much of last year with an ankle injury, was rarely able to place any pressure on Myskina in their baseline rallies.