Seamer Atkinson Adds to the English team's Injury Concerns.
'Significant concern' for England after Atkinson goes off due to a hamstring issue.
The pace bowler increased England's injury problems upon exiting the field early on day two in the Melbourne Test versus the Australians.
Atkinson experienced discomfort in his left leg after the final ball of the fourth over during the morning session.
The touring camp stated the 27-year-old felt some "soreness" and would spend time on the sidelines in order to be assessed "over the next few hours".
The concluding match in this Ashes battle at the SCG begins on Sunday, 4 January.
The visitors have already lost fast bowlers Mark Wood to a knee injury and Jofra Archer with an abdominal strain on the current trip.
Matthew Fisher was called up as cover for Wood.
Atkinson struggled in the opening two Tests, taking just three wickets.
He was omitted from the previous Test, then recalled for the Melbourne Test as Archer's replacement.
Surrey's Atkinson showed better form in Melbourne, claiming a couple of wickets in Australia's first innings, and scoring 28 runs as a batsman being one of only three England players who passed ten runs.
After bowling one over at the end of day one, he returned the next day and had nightwatchman Scott Boland caught behind.
However, at the end of that over, he bowled a variation to the batsman and promptly felt at his leg.
Atkinson was recalled for the Boxing Day Test following his omission the Adelaide game.