Tennis: Caroline Wozniacki stunned by Bianca Andreescu at ASB Classic in Auckland

Bianca Andreescu celebrates her win over Caroline Wozniacki. Photo / Photosport

Caroline Wozniacki has crashed out of the ASB Classic, with a shock 6-4 6-4 loss to Canadian qualifier Bianca Andreescu on Thursday night.

Statisically speaking, the defeat at the hands of the world No 152 was Wozniacki's most unlikely loss in more than five years.

While most pundits were confidently looking forward to a Wozniacki-Venus Williams clash in the quarter finals, the Canadian confounded the form book with the performance of her life.

The 18-year-old Andreescu combined savage power, superb athleticism and fine placement, together with astute shot making.

But it was still a shock.

Wozniacki hadn't lost to a lower ranked player in more than five years, since she was upset by world No 196 Petra Cetkovska in the second round of Wimbledon in 2013.

But Andreescu had only once previously beaten a player inside the top 50, since she turned professional in 2016.

But for long periods of the match she couldn't do anything wrong; she hit winners from all angles, forced the Dane to overplay her hand and fearlessly charged the net, with superbly volleying technique.

She also achieved what is generally considered impossible; catching out the fastest player on the WTA Tour with a drop shot, on multiple occasions, even to save break points.

The first set was a thriller. Both players had traded breaks midway through the set, though the Canadian had showed her resolve by defending five break point opportunities in the eighth game, before Wozniacki converted the sixth. But the Canadian edged ahead with another break, and then converted her first set point when Wozniacki sent a nervous backhand long.

The tension only increased in the second set. By this stage both players had taken medical timeouts, and on at least two occasions the games stretched on past 10 minutes.

The clock ticked past 11pm, but no one could leave, enraptured by the match of the tournament so far.

Despite struggling with a back injury, Andreescu achieved the vital break to got up 5-4 in the second set, as she continued to go for everything. She then forced a match point, and after another long rally of unbearable tension, sent her most important forehand winner to clinch the match at 11:22pm.