Novak Djokovic confirmed on Wednesday that he's optimistic of starting for Serbia against Kazakhstan on Friday in their Davis Cup World Group first-round tie after dealing with an infection in both eyes.
The world number one developed the problems last week in Dubai, where he was forced to quit his quarter-final against Feliciano Lopez.
Reports indicated that he could have picked up his case of conjunctivitis during a photo shoot in a water park swimming pool 10 days ago.
"All is going well regarding my recovery and I am optimistic about playing in the tie," Djokovic said. "I was very skeptical about playing at first, but I still have two days left to adapt to the light and other indoor conditions and hopefully I will be OK."
Serbia are keen to try and repeat history after winning the worldwide team competition in 2010, with Djokovic leading the effort.
Meanwhile, the fitness of Dubai semi-finalist Nick Kyrgios was becoming more of a mystery after the Australian made a brief appearance on court at Kooyong club this week in the run-up to their tie with the United States.
Kyrgios came down with a virus in Dubai and was unable to complete his semi-final against Stan Wawrinka. He hit for 30 minutes in Melbourne this week but is no sure thing for a start on Friday.
There is now serious speculation that just-retired Lleyton Hewitt, 35, could step into a playing captain's role for the tie.
Any unscheduled return for Hewitt would place the two-time grand slam winner alongside Bernard Tomic (dealing with a wrist niggle) in singles against the 32-times champion US with John Isner, Jack Sock and the Bryan twins.
"We'll have to see now, but he hit really well and he seems good," team coach Jason Stoltenberg said of Kyrgios, who has been quarantined away from the team under Hewitt's orders.
"(Hewitt's) enjoyed the hitting, though. He thought he was retired and he's hitting more than these guys. It's probably the first time a captain's had to get out and prepare as if he may play," the coach told The Age.
"He's a great team man and he'll do whatever he needs to do, whether that's playing or sitting on the side. We don't expect he'll play. But we'll have to wait and see in the next 24 hours. He thinks ahead and he's pretty organised. So I'd say in his mind he's just covering all his bases."