Agnieszka Radwanska hopes coach Martina Navratilova can help her with the "really small details" needed to win a maiden grand slam title.

The sixth seed overcame American Varvara Lepchenko 6-0 7-5 to reach the Australian Open fourth round on Saturday.

Radwanska has reached at least the quarter-finals at Melbourne Park in every year since her third-round exit in 2010.

But the 25-year-old has failed to breakthrough, with her runner-up appearance at Wimbledon in 2012 the closest she has come to winning a major.

Navratilova began coaching Radwanska at the end of last year and the Pole hopes the 18-time grand slam winner can help her finally win one of her own.

"On this level, I think it's just really small details that are very important," Radwanska told a media conference after beating Lepchenko.

"Of course everybody can play great tennis but if you want to win a match or grand slam, you really have to do everything right.

"That's what we're working on, just to focus on very important things and talking on and off the court, and just to figure out everything just to win those seven matches in a row."

Radwanska, who has dropped just nine games in three rounds, will face Venus Williams in the last 16.

Asked if she felt like she could beat anyone, Radwanska said: "I hope so but of course every match is different story and different opponents, so sometimes you play the opponent that you play.

"You never know. That's sport."