Perth - Australian paceman Ryan Harris is battling a sore knee, with reports on Thursday saying he was in doubt for the third Ashes Test against England.
The 34-year-old has been a crucial part of the attack that has fired Australia to a 2-0 lead over their arch-rivals, but he reported stiffness during the second Adelaide Test.
Channel Ten television said he was a doubt for the Perth Test starting on Friday, in which Australia can take an unbeatable 3-0 lead in the five-match series.
"Ryan Harris has had an ongoing knee issue throughout his career which we manage after each Test he plays," a Cricket Australia spokesman said.
He added that the Queensland quick, who has bowled 67.4 overs in this Ashes series, with eight wickets at 20.25, would train on Thursday.
If he does not recover, James Faulkner, who was 12th man in Brisbane and Adelaide, is a contender to come into the side, while Doug Bollinger and Nathan Coulter-Nile are on standby.