Nick Kyrgios of the Australia Green team hits a return against Alexander Zverev of Germany during their first session men's singles match on day one of the Hopman Cup tennis tournament in Perth on January 3, 2016. AFP PHOTO / Tony ASHBY -IMAGE RESTRICTED TO EDITORIAL USE - NO COMMERCIAL USE- / AFP / TONY ASHBY (Photo credit should read TONY ASHBY/AFP/Getty Images)

Nick Kyrgios has withdrawn from the Kooyong Classic due to a foot complaint.

Kyrgios won the first set against Belgium's David Goffin, before retiring hurt trailing 3-2 in the second set after receiving treatment on his foot earlier in the match.

Kygrios apologised to both Goffin and the crowd, but the young Aussie is expected to be fully fit for the Australian Open, which is less than a week away.