British hope Andy Murray remains on course for a place in the Australian Open quarter-finals for the first time in his career following his 7-5 6-1 6-4 third-round success against Florent Serra – but has warned of a much tougher challenge against either Gael Monfils or John Isner in the fourth round (4/1 4th Round – Murray Stage Of Elimination).

The 22-year-old was tested in the opening exchanges by world number 64 Serra but looked much more comfortable as the match unfolded.

The fifth raced raced to a 3-0 lead before finally edging the first set whereas the second set was a lot more routine.

The young Scot survived another wobble in the third to wrap up his third consecutive straight-sets win.

“The first set was a bit closer than it needed to be. I had chances to go 4-0 up,” he told BBC Sport. “I am delighted to win in straight sets.”

He will now face the winner of the game between Monfils, seeded 12th, of France and Isner of America.

“Both are really tough players,” he added. “Monfils is one of the best athletes on the tour – he can chase every ball down and is very unpredictable.

“Isner is tough. He won last week and beat Andy Roddick at the US Open. He is 6′9″ and causes people problems.”

Don’t miss your chance to check out Totesport.com’s Australian Open match betting markets on Day 5 at Melbourne Park.