Leylah Annie Fernandez won 6-1, 4-6, 7-6 (3) over Zheng Qinwe on Wednesday in Monterrey with difficulty.
The 19-year-old Quebec continues her journey to the quarterfinals after a fight that lasted 2:42 hours, as she tries to defend her title in this tournament.
Fernandez will now face either Mayar Sherif or another Chinese man, Qiang Wang.
Fernandez broke her opponent in her first serve and from the moment she led 2-1, she easily reached a first set in her pocket, without conceding any other game to the 77th racket in the world.
The Chinese did not play inspiringly in the first set, they often offered too many balls right in the middle and had no consistency, but things got tighter for the second Fernandez afterwards. The match became much more competitive and Quebecer stumbles in the end with the break.
In the final set, Fernandez almost threw her serve to follow 4-2 facing no less than three break points, but saved the furniture before later having to claim the tie break, which prevailed.
