There is a carnival atmosphere at Melbourne Park on day eight of the Australian Open as home tennis fans celebrate Australia Day

On court, British teenager Laura Robson begins her first campaign in the Australian Open girls' singles against Christina McHale

Robson, the 2008 junior Wimbledon champion, is given a tough test by her more experienced opponent but seals a 7-5 6-3 victory

It is an all-French clash on Rod Laver Arena as sixth seed Gilles Simon takes on 12th seed Gael Monfils

The match comes to an abrupt end as a wrist injury forces Monfils to retire after three sets

Unseeded Spaniard Carla Suarez Navarro is through to the last eight, beating 21st seed Anabel Medina Garrigues 6-3 6-2

Fourth seed Elena Dementieva racks up her 14th straight win of 2009 as she beats Dominika Cibulkova 6-2 6-2

Jie Zheng has a nasty fall when playing Svetlana Kuznetsova and the injury to her left wrist eventually forces the Chinese player to retire

Serena Williams is in trouble as she drops the opening set to Belarusian Victoria Azarenka

But the heat plays a part as Azarenka suddenly wilts in the second set and she too has to retire

World number one Rafael Nadal races into a two-set lead over Fernando Gonzalez on Rod Laver Arena

Gonzalez endures a torrid time as Nadal dominates from the outset

Nadal wraps up a 6-3 6-2 6-4 win and is yet to drop a set in the tournament

Andy Murray starts well against Fernando Verdasco but then loses his way in a poor second set

Murray moves ahead with a much stronger effort in the third set but is pegged back again in the fourth and faces a decider

It is Verdasco who makes the decisive breakthrough in the fifth set and the Spaniard serves out for a famous victory

As if to rub it in, Jo-Wilfried Tsonga tries out Andy Murray's trademark celebration as he races to victory over James Blake

Blake serves for the third set but can't close it out and Tsonga seals a 6-4 6-4 7-6 (7-3) victory

Tsonga stays on track for a repeat of last year's semi-final against Nadal - much to the delight of his glamorous support camp