US Open champion Naomi Osaka emerged from the jaws of defeat against Hsieh Su-wei to reach the Australian Open last 16.
Japanese star Osaka was down a set and 4-1 in the second before rallying to a 5-7 6-4 6-1 win after almost two hours in Melbourne on Saturday.
Osaka - aiming to become the first woman to win successive grand slams since Serena Williams claimed the 2014 US Open followed by the Australian Open, French Open and Wimbledon in 2015 - appeared set to exit Melbourne Park.
That was until the fourth seed, who was uncharacteristically frustrated and error-riddled in the first set, reeled off five successive games to force a decider and she never looked back.
It was a high-energy encounter on Margaret Court Arena, where both players went toe-to-toe, with Hsieh refusing to take a back step to Osaka.
The enthusiastic and aggressive Hsieh lost her way temporarily as Osaka reeled off four successive games with the end of the set looming, having been broken in the sixth game.
Hsieh, however, stopped Osaka from serving out the first set - the 28th seed from Chinese Taipei frustrating her more fancied opponent as the unforced error count grew to 20 under the Melbourne sun.
Consecutive sprayed forehands, a shot into the net and a wide backhand typified Osaka's set as Hsieh closed out the set.
The usually calm and composed Osaka - who has never reached the Australian Open quarter-finals - threw her racquet at the end of the set, earning a code violation for unsportsmanlike conduct.
Osaka had more to be upset about in the second set, falling 3-0 and 4-1 behind, but she suddenly clicked into gear and won five successive games to avoid elimination and 10 of the next 11 to earn a showdown with either Anastasija Sevastova or Wang Qiang.
Osaka  bt Hsieh  5-7 6-4 6-1
Osaka - 41/42
Hsieh - 28/31
Osaka - 8/1
Hsieh - 0/6
BREAK POINTS WON
Osaka - 7/11
Hsieh - 4/15
FIRST SERVE PERCENTAGE
Osaka - 61
Hsieh - 73
PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE
Osaka - 63/51
Hsieh - 59/33
Osaka - 102
Hsieh - 89