(Updates with Wang Xinyu's win over Alexandrova)

WUHAN, Oct 11 (Reuters) - World number four Coco Gauff earned her 50th win of the year in WTA main draw matches as she beat Magda Linette 6-0 6-4 in the quarter-finals of the Wuhan Open on Friday, potentially setting up a semi-final clash with top seed Aryna Sabalenka.

Former U.S. Open champion Gauff, who has made some grip changes with new coach Matt Daly, made eight double faults in the match but was dominant with her returns.

"I played well ... overall, maybe two bad games," 20-year-old Gauff said in the post-match interview after extending her winning streak to nine matches.

An error-prone Linette came close to breaking Gauff twice in the first set. But Gauff saved four break points to hold both games, winning 14 of 21 return points as the Polish former Australian Open semi-finalist fell to a bagel.

Gauff faced a tougher battle in the second set but one of Linette's 22 unforced errors gave the American an edge in the seventh game as she got the only break of the set, which sealed the win.

Guaff will play the winner of Friday's third quarter-final -either Belarus' Sabalenka, the current U.S. Open champion, or Poland's Magdalena Frech - on Saturday.

"I've played them both before, they're tough opponents," Gauff said.

Third seed Jasmine Paolini of Italy plays fifth seed Zheng Qinwen from China in another quarter-final later in the day. The winner will take on China's Wang Xinyu, who beat Russia's Ekaterina Alexandrova 4-6 7-5 7-6(6) in the last eight.

(Reporting by Chiranjit Ojha in Bengaluru; Editing by Clarence Fernandez and Edwina Gibbs)

((chiranjit.ojha@thomsonreuters.com;))