Melbourne: Top seed Serena Williams powered into the Australian Open fourth round on Saturday, but only after sister Venus inspired her to shake of a sluggish start against Ukrainian 26th seed Elina Svitolina.


Serena Williams celebrates her win over Elina Svitolina. Pic/AFP 

The 18-time Grand Slam champion conceded her first set of the tournament to Svitolina, continuing a run of slow starts, before Venus' hard-fought run into the final 16 at Melbourne Park convinced to her to knuckle down.