Djokovic had (more) nice words to Kei Nishikori in Shanghai.
"I would like to use another opportunity to congratulate Kei for his outstanding career, a lot to be proud of. He, unfortunately, was injured quite a lot and struggled throughout his career to keep fit. I think this probably might be the only regret that he has, that he wasn't able to maybe stay healthier longer.
“Because he was, when he was playing his best tennis, he was a top-5 player. Incredibly quick, so talented, the striking and timing of his shots was exceptional. Of course, him retiring in his country, in front of his people, is something that I think every player really dreams of, so I'm sure that he enjoyed his farewell there.”