World number one Carlos Alcaraz beat Taylor Fritz at the Japan Open, before pulling out of this week's Shanghai Masters.
Alcaraz secured his eighth ATP title of the year in Tokyo after 6-4 6-4 win, reported BBC.
But he then announced that he has withdrawn from the tournament in Shanghai, which starts on Tuesday, writing on Instagram that "the best decision is to rest and recover".
"Unfortunately, I've been struggling with some physical issues and, after discussing with my team, we believe the best decision is to rest and recover," he wrote.
The Spaniard twisted his left ankle during his opening-round match in Tokyo last Thursday.
But he showed no signs of an issue during the final, broke for 5-4 and served out for the first set against Fritz.
Fritz twice required treatment to his left thigh before returning for the second and Alcaraz seized the opportunity to pile on the pressure.
The American was broken twice and trailed 4-1 but did offer some resistance in the closing stages, chalking one of those off, but didn't have enough to stop the six-time Grand Slam champion.
Since losing against Jannik Sinner at Wimbledon in July, Alcaraz has won three successive ATP titles - the Cincinnati Open, US Open and Tokyo Open.
