MELBOURNE: Paula Badosa fended off a Marta Kostyuk comeback in an engrossing baseline battle to reach the fourth round of the Australian Open for the first time with a 6-2 5-7 6-4 victory on Friday.

The in-form world number six looked to be cruising at a set and break up on Margaret Court Arena when her talented 19-year-old Ukrainian opponent found her range and clawed her way back into the contest.

The pair traded ferocious stroke for ferocious stroke from the back of the court but Kostyuk's accuracy betrayed her at key moments in the third set and Badosa finally got the job on her fifth match point after more than two hours on court.

US Open champion Raducanu crashes out of Australian Open

The Spanish eighth seed, riding the momentum from a title triumph in Sydney last week, will next face the powerful American Madison Keys or China's Wang Qiang for a place in her second Grand Slam quarter-final.