Lleyton Hewitt remains confident Nick Kyrgios will be fit and healthy for Australia's Davis Cup first-round tie against the United States on Friday, despite revealing the youngster is being laid low by a virus.
Concerns over Kyrgios' fitness emerged after he retired against Stan Wawrinka in the semi-finals of the Dubai Tennis Championships last week, though it is an infection and not back and hip issues hampering the 20-year-old.
Kyrgios has been unable to link up with his Australia team-mates in Melbourne, grounded in Canberra instead.
But captain Hewitt reiterated his confidence that Kyrgios will be ready to face American John Isner on the grass-courts at Kooyong.
"He's just had a bit of a virus," Hewitt said.
"At the moment, he's just taking it easy and trying to get over that 100 per cent.
"And then he'll be right to go.
"Obviously I didn't want him right around the other boys right at the moment if he's infectious as well.
"It's kind of precaution more than anything. He'll be right to go."