Serena Williams lavishes praise on Ash Barty with showdown looming

Serena Williams has lavished Ashleigh Barty with praise as the two heavyweight contenders hurtle towards a blockbuster Wimbledon quarter-final.

In a rematch of last year's semi-final against Julia Goerges, Williams again reigned to move ominously into the last 16 at the All England Club for the 16th time with a 6-3 6-4 third-round win over the German.

Without a match since the the French Open, the 23-times grand slam champion looked rusty in her first two outings, but stepped it up on Saturday to edge to within a likely last-eight showdown with Barty.

The 37-year-old has a habit of slowly working her way into the majors and will be an overwhelming favourite to take out Spanish veteran Carla Suarez Navarro on Monday.

With Barty cruising through to the fourth round without dropping a set and odds-on to continue her charge against unseeded American Alison Riske, Australia's world No.1 is tipped to face her sternest test yet against Williams.

Bidding for a record-equalling 24th major, and eighth Wimbledon crown, Williams is full of respect for Barty, admitting she'd been keeping a close eye on the top seed's progress.

Williams and Barty first met when the Australian was a teenager at her home slam in 2014.

"I've always from the day I played her in Australia had a tremendous amount of respect for her game," Williams said.

"I just thought she's just a beautiful player. She has great technique. I love that.

"I'm really a technical player. I like when people have a beautiful game and they do the right techniques. It's so right up my alley.

"I've seen her play a lot recently, too. Like I always say, she's just someone in the locker room that you just always root for.

"But in general I have been watching her game because I know that she's a force to be reckoned with. So I've been watching a lot."

With Barty having not dropped a set in her past 10 matches, a duel with Williams appears inevitable.

Not that Barty was prepared to assume as much after her 6-1 6-1 rout of British wildcard Harriet Dart.

"I will give the athlete's answer and say: I'm just going to worry about Alison first," the French Open champion said when asked about the prospect of facing the former world No.1.

Suarez Navarro booked her date with Williams with a 6-3 6-3 win over Lauren Davis, the American qualifying lucky loser who had ended Angelique Kerber's title defence.

Riske upset Swiss world No.13 Belinda Bencic 4-6 6-4 6-4 to ensure Barty's seed-free path to at least the last eight.

Dual Wimbledon winner Petra Kvitova continues to loom as a potential semi-final threat to Barty and Williams after marching on with a 6-3 6-2 dispatch of Poland's Magda Linette.

Like Barty, sixth-seeded Kvitova, champion in 2011 and 2014, has yet to drop a set.

Kvitova will play resurgent world No.18 Johanna Konta after Britain's last hope eliminated American ninth seed Sloane Stephens 3-6 6-4 6-1.

The other fourth-round battle in the top half of the draw features Belgian Elise Mertens, the 21st seed, against Czech Barbora Strycova.

Mertens progressed with a 6-2 6-7 (9-11) 6-4 victory over China's Wang Qiang, while Strycova bounced out world No.4 Kiki Bertens 7-5 6-1.