Former world champion Cadel Evans has been ruled out of the men's individual time trial because he is exhausted.
The Australian won the Tour de France in 2011
but endured a
difficult defence of his yellow jersey this year,
finishing 15 minutes behind winner Bradley Wiggins in seventh.
Evans, 35, competed in
Saturday's road race
for Australia but finished 79th.
Cycling Australia said two doctors have "confirmed he is fatigued and will not recover in time for Wednesday".
The Australian Olympic Committee said Evans will not be replaced in the time trial, so Michael Rogers will be the only Australian to take part.