David Goffin overcomes Dominic Thiem in four sets
The 11th seed will face either Bulgaria's Grigor Dimitrov or Uzbekistan's Denis Istomin next.
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"From the third set there was some cloud cover but the first two sets were really tough," said the Belgian, who reached the quarter-finals by beating Austria's Dominic Thiem.
"I'll be watching (Grigor Dimitrov play Denis Istomin) from the ice bath or the jacuzzi so it's okay."
Goffin becomes the first Belgian player to reach the last eight of the Australian Open.
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