Stanislas Wawrinka has played down his straight-sets victory over Kei Nishikori by insisting that his opponent provided him with a difficult match.
The defending champion hit 20 aces and 34 winners as he overpowered the fifth seed on the Rod Laver Arena, but the Swiss number two struggled to serve out the win.
Wawrinka squandered a 6-1 lead in a third-set tie-break before finally progressing on his sixth match point, and the world number four has admitted that nerves kicked in during the end of the contest.
The 29-year-old said: "I'm still nervous even after the end of the tie-break. There is no easy match even from the first round. I am playing well and I'm happy to be back playing the semi-final."
Wawrinka will play the winner of the encounter between Novak Djokovic and Milos Raonic in the semi-finals.
