Sharapova happy with serving display at Aus Open

The Russian was pushed in a 7-5 7-5 win over Belinda Bencic in the fourth round on Sunday, sending down 21 aces in the gruelling clash.

Sharapova has served a tournament-leading 52 aces so far, as well as 17 double faults.

The five-time grand slam champion said her display was strong against Bencic, despite putting in just 47 per cent of first serves.

"I thought I served quite well," Sharapova said.

"I found my spots; hit the line many times today. That was important."

Sharapova will have to serve exceptionally well against Williams, who has won 18 of their 20 matches and the past 17 – including last year's final in Melbourne.

The 28-year-old said she was simply targeting improvement ahead of another meeting with Williams.

"It's not like I think about what I can do worse. You're always trying to improve. I got myself into the quarter-final of a grand slam," Sharapova said.

"There is no reason I shouldn't be looking to improve and to getting my game in a better position than any other previous round. It's only going to be tougher, especially against Serena."