By Sudipto Ganguly
MELBOURNE (Reuters) - Unseeded Russian Anastasia Pavlyuchenkova won a marathon three-setter against American fifth seed Sloane Stephens 6-7(3) 6-3 6-3 to reach the Australian Open quarter-finals on Sunday and match her best show in Grand Slams.
Stephens gave up a 4-1 advantage in the opening set to win it on a tiebreaker but Pavlyuchenkova rallied once again from an early break down to convert her third set point and level the match.
The 2017 U.S. Open winner then lost steam as the world number 44 converted her second match point to seal the contest in two hours and 32 minutes.
For a place in the semi-finals, Pavlyuchenkova will meet another American in unseeded Danielle Collins, who earlier thrashed 2016 champion and second seed Angelique Kerber 6-0 6-2.
(Reporting by Sudipto Ganguly; editing by Clare Fallon)