Fast bowler Gus Atkinson Compounds England's Fitness Problems.
'Significant concern' for the touring side as Atkinson leaves the field suffering a hamstring problem.
The pace bowler added to England's injury problems upon exiting the playing area during Saturday's play of the fourth Ashes Test versus the Australians.
Atkinson felt a problem in his left hamstring post-delivery that he bowled at the MCG.
The touring camp indicated Atkinson had experienced "tightness" and would spend time on the sidelines in order to be assessed "over the next few hours".
The concluding match of the series in Sydney gets underway on Sunday, 4 January.
The visitors have already lost fast bowlers Mark Wood due to knee trouble and another paceman to a side strain on this Ashes tour.
A replacement bowler was brought into the squad to provide backup.
Atkinson struggled during the first two matches, claiming a mere a handful of scalps.
He was left out of the third Test, then recalled for the Melbourne Test in the playing XI.
Surrey's Atkinson performed better in the fourth Test, claiming a couple of wickets with the ball, then making 28 with the bat as one of just three teammates to get into double digits.
Post a single over late on the first day, he came back on Saturday morning and had nightwatchman taken by the wicketkeeper.
Yet, towards the conclusion of the fifth over, he delivered a change of pace to the batsman and suddenly grabbed at his leg.
The English bowler was recalled for the Boxing Day Test after being left out the previous Test.
