Serena Williams fought back from a set down to beat number 26 seed Elina Svitolina in the third round of the Australian Open.

The Ukrainian started the match in the perfect fashion with a break in the first game, which she then followed up with another to take a 4-1 lead in the set.

Williams staged a revival following a slow start with two breaks of her own, but Svitolana managed to stave off the 33-year-old to take the set 6-4.

The five-time champion's response was immediate as she produced her best tennis to hit back at the 20-year-old as she broke her twice in the second set to power into a 4-0 lead.

Svitolina tried to claw her way back with a break and a hold, but Williams broke her again to claim the second set 6-2 to send the match into a decider.

The number one seed took the initiative as she powered her way through the Ukrainian with an excellent array of shots around the court as the 20-year-old began to wilt under the strain.

Williams broke down Svitolina's resistance once more with a break despite the Ukrainian's best efforts to cling on in the match. The world number one clinched her victory with another break of serve to take the set 6-0.

The American will now play number 24 seed Garbine Muguruza in the fourth round of the competition.