Djokovic battles through pain to reach his 11th quarterfinals in Shanghai

The extreme physical toll, fatigue, and the ankle problem, forced Djokovic to take long pauses, stooping down to rub his left foot, in between points and saw him collapse to the floor after losing the second set to Munar.

And he did not participate in the usual on-court interview following the lengthy battle, only addressing the Shanghai crowd at the packed Stadium Court of Qizhong Tennis Center with a few Chinese phrases.

"Xie xie! Wo ai ni men!" Djokovic said, which translates to "Thank you! I love you guys!"

He then left the court and his adoring fans for treatment.

According to an ATP news release, Djokovic's physical discomfort had to be attended by tournament doctors and ATP physios right after the match and he was advised to rest and recover before his next match on Thursday.