Fast bowler Atkinson Compounds England's Fitness Worries.
'Major setback' for the touring side as Atkinson is forced off suffering a hamstring problem.
The pace bowler added to the fitness woes of the England squad after leaving the playing area early on day two in the Melbourne Test in the Ashes series.
Atkinson pulled up with his left hamstring post-delivery that he bowled on Saturday.
The touring camp indicated the 27-year-old felt some "soreness" and was to take time away from the action for further assessment "during the day".
The concluding match in this Ashes battle beginning on 4 January starts this coming Sunday.
The visitors have been without strike bowlers Mark Wood due to knee trouble and another paceman because of a side injury on the current trip.
A replacement bowler was brought into the squad as cover for Wood.
The seamer had a tough time during the first two matches, taking just a handful of scalps.
He was left out from the previous Test, only to be brought back for the fourth Test in the playing XI.
The county bowler improved at the MCG, bagging two scalps during the host's first knock, before adding 28 while batting as one of just three teammates who passed ten runs.
Following a brief spell in Australia's second innings, he resumed on Saturday morning and removed Scott Boland edging to the keeper.
However, towards the conclusion of his spell, he bowled a variation to the batsman and promptly felt at his leg.
Gus Atkinson was recalled for the Boxing Day Test having missed the previous Test.
