Murray handed final Melbourne warm-up

British No 1 to feature in Kooyong Classic ahead of next week's Australian Open

Andy Murray will play a match at the Kooyong Classic exhibition in Melbourne tomorrow, tournament organisers have announced.

The British No 1 had been touted as a potential replacement for Roger Federer following his withdrawal at the weekend but that spot has gone to Ivan Ljubicic. Murray, who earlier this week dropped to No 5 in the world, will instead play a match outside of the round-robin format against an as-yet unnamed opponent.

The 22-year-old's main Australian Open preparation came at last week's Hopman Cup, where he played singles and mixed doubles with Laura Robson as the British pair reached the final, but Murray was keen for another competitive match ahead of the first grand slam of the season.

Ljubicic joins Novak Djokovic, Robin Soderling, Juan Martin del Potro, Fernando Verdasco, Fernando Gonzalez, Jo-Wilfried Tsonga and Tommy Haas in the eight-man field.

In Sydney, Serena Williams started her 2010 season in the same devastating fashion in which she ended 2009, thrashing Spain's Marie Jose Martinez Sanchez 6-1, 6-2 in the second round of the Sydney International yesterday.

Playing her first match since beating older sister Venus in the final of last year's Tour Championship, Williams showed why she remains the woman to beat at this month's Australian Open with a powerful display.

The world No 1was not at her absolute best after a two-month break and struggled with the scorching temperatures at the Olympic centre, but could not have been happier with her form leading into the first grand slam of the year.

"I felt all right. Obviously I don't feel my best, but that's what the game is all about, taking it one match at a time and just doing the best that you can," she said.

Russia's Dinara Safina, who lost last year's Australian Open final to Williams, also opened her new season with a win but had to work much harder before toppling Polan's Agnieszka Radwanska 7-5, 6-4 to advance to the quarter-finals.

Safina lost the first five games of the match but just when the world No 2 looked to be in trouble, she rebounded and seized control of the contest. "It was a little bit of slow start, but it was a winning start," Safina said. "It's not easy to play against her. She's a top 10 player and she plays very smart."