WUHAN (AFP) - Venus Williams won her second tennis title of the season at the Wuhan Open in central China on Saturday, after Garbine Muguruza retired in the second set.

Williams took the first set 6-3 and was then handed the title by the fifth-seeded Spaniard after 53 minutes, three points into the second set.

Wimbledon finalist Muguruza - ranked world No. 8, 16 places ahead of American veteran Williams - had a tough semi-final against Germany's Angelique Kerber, winning in straight sets but falling during the closing tie-break and injuring her ankle.

"It's a sad day I had to retire. Sometimes your body's not recovered," the 21-year-old said on court after the match.

Williams, 35, who also looked stiff on court the day after a gruelling semi-final against her sister Serena's nemesis Roberta Vinci, conceded that she would have had a tough match against Muguruza if she had been on form.

"I probably wouldn't have had many chances if you had been feeling well," Venus said in an on court interview.

Muguruza would have qualified for the WTA Finals in Singapore later in October if she had won.