Djokovic dominated Japan 's Kei Nishikori in a one - sided quarter - final to set up a semi-final meeting with David Ferrer .
Djokovic beat Nadal in last year 's final to claim his third title in the Italian capital .
Djokovic , who beat Nadal in last year 's final to claim his third title in the Italian capital , dominated Japan 's Kei Nishikori in a one - sided quarter - final to set up a semi-final meeting with David Ferrer .