Live updates: ''The biggest day in ASB Classic history' - Serena Williams, Caroline Wozniacki and Coco Gauff

Join live updates of the ASB Classic as quarter-final spots are on offer in an action-packed day.

ASB Classic tournament director Karl Budge has labelled Thursday's schedule as the biggest day in the event's history.

There have been some stellar fields in the past, but today's second round action is hard to top, with Serena Williams, former World No 1 Caroline Wozniacki, two time defending champion Julia Goerges and 15-year-old American sensation Coco Gauff, who is tipped to become the next Serena, if she continues her current trajectory.

Perhaps the closest over the last decade was the 'super Tuesday' in 2016, when three former World No 1's (Wozniacki, Ana Ivanovic and Venus Williams) were in action on Stanley Street.

"I think whenever you have Serena it takes it to another level," said Budge. "And then throw in Coco Gauff – how much did her Wimbledon run last year captivate people all over the world?"

"I'm biased, but I think today is unrivalled and I don't know if this event gets the kudos it deserves in terms of true global star power that comes here.

These are household names wherever you go in the world and the biggest name; I don't think there has ever been a bigger female athlete than Serena. Supplement that with Caroline Wozniacki in potentially her last ever match at a WTA tournament, Gauff and our two time defending champion. It's a pretty special day. "

In our social media age, the number of eyeballs worldwide that follow the fortunes of the today's field is staggering.

Williams, Wozniacki and Gauff have a combined reach of 35 million followers – across Instagram, Twitter and Facebook.

That's a figure that would surely dwarf the entire All Blacks, Black Caps and Silver Ferns squad put together.

They are also some of the biggest earning females athletes in the history of sport, raking in more than US$137 million ($207 million) in their career.

Williams is the largest by far ($139 million) but Wozniack is fourth among active players ($52.18 million), only behind the Williams sisters and Maria Sharapova while Goerges has hauled in $14.48 million across more than a decade on tour.

And, if all the favourites progress, Friday could be even bigger, with Canadian Eugenie Bouchard and American youngster Amanda Anisimova in action.

Anisimova was particularly impressive on Wednesday night, in the most complete all round display so far.

She made short work of Russian Daria Kasatkina, the world No 70 who reached the top 10 towards the end of 2018.

It was expected to be a close match, but was over in 73 minutes, Anisimova breaking the Russian seven times in her 6-2 6-4 victory.

Anisimova's stand and deliver backhand was particularly lethal, and though she is flying under the radar, the 18-year-old is one of the top contenders for the title.