Novak Djokovic vs Kei Nishikori: 3 keys to the match

(Photo credit: Keith Allison)

Djokovic and Nishikori, who have met 16 times in the past, will renew their rivalry in the US Open semifinals on Friday. Djokovic comes into the match on the back of triumphs at Wimbledon and in Cincinnati where he completed the Career Golden Masters. He also scored a 13th straight win over Nishikori at the Championships in the quarterfinals. But, they have met in a US Open semifinal before and Nishikori was the victor. RealSport look at three keys to this contest.