Frustrated at his inability to make inroads on the world No.71’s serve, Ruud realised he needed to fight fire with fire to counter his 193cm opponent’s all-court aggression.
It was to little avail. With a set in hand, Zhang was in full flight and he threatened to take the reins early in the second set with five straight winners.
His only poor game of the set came at the most inopportune time, broken to love as Ruud squared the match.
It proved a pivotal moment. For the best part of the opening two sets Zhang was the better player but Ruud never went away.
He blew open the second set and imposed his heavy whipping forehand to take control as his opponent’s errors mounted in the fourth.
A fourth-round date with either Nicolas Jarry or Marcos Giron was set after two hours and 35 minutes.