Nick Kyrgios has played down concerns over his knee injury, following a 6-2, 6-2 loss to American Jack Sock at the Hopman Cup last night.

Kyrgios was clearly hampered during the match, as he moved around the court gingerly and slowly.

The youngster withdrew from the mixed doubles match with Daria Gavrilova, with an eye on the Australian Open, beginning Monday week.

However, Kyrgios said the injury will not affect his preparation for the first Grand Slam of the year.

"It is not terrible but it is not great... just the start of some boney stuff in my knee," Kyrgios said.

"Obviously it was hindering me a little bit out there but I didn't want to do anything to make it worse.

"I just need to rest now and a couple of days without the load and I should be back to normal.

"I've got four days now to go home, see my physio, ice it and rest it and that is ample time for it to settle down."

The Aussies are now out of the Hopman Cup, going down 2-1 to the United States, despite  Daria Gavrilova's 6-3, 4-6, 7-5 win over Coco Vandeweghe.