Matt Prior has been ruled out of England final Ashes warm-up match against the Australian Invitational XI.
Prior suffered the injury on the last day of the draw with Australia A in Hobart, with England's vice-captain unable to take to the field for the final session.
That saw Joe Root forced to stand in as wicketkeeper, however his fellow Yorkshireman Jonny Bairstow will take the gloves in Sydney.
England, though, remain confident that Prior will be fit for the first Test against Australia in Brisbane, which gets underway on November 21.
"Matt Prior has been ruled out of the tour game starting on Wednesday with a low-grade tear of his left calf," an ECB spokesman said.
"He will continue his rehab and recovery with a view to being picked for the first Test."
Prior added he would be working hard to ensure he was fit to tackle the Aussies.
He wrote on Twitter: "Obviously very disappointed to be missing the game at SCG but doing everything possible to be ready for the 1st Test at the Gabba! #ashes."
Prior's team-mate Ian Bell is confident that the wicketkeeper will be fit in time.
"It is not ideal but it gives a good opportunity to Jonny Bairstow," he said.
"We have seen in the past how important it is to get the whole of the squad playing before the series start. With five Tests it is important everyone gets some cricket under their belts.
"Matt has been a key part of our success over the past few years and obviously we want him to get recovered as soon as possible.
"There's still a bit of time. He has got himself in fantastic condition for this tour and he will be very good with his rehab so I have got every faith he will be fit for Brisbane."
There seems to be better news for England regarding Kevin Pietersen, who has had a scan after also giving England an early injury scare.
But with the start of the Ashes only 10 days away, it seems the recurrence of Pietersen's old problem with bone bruising in his right knee - he missed three months earlier this year - is not going to disrupt his preparation.
Pietersen was set to take full part in indoor training on Monday at the SCG, where pouring rain stopped England using the outdoor facilities.
Bell was able to confirm his fellow batsman is back on track, having diverted to Melbourne on Sunday - while his team-mates headed direct from Hobart to Sydney - to have a cortisone injection and his scan.
Asked how Pietersen is, and his chances of playing in the four-day match starting on Wednesday, Bell said: "Really well.
"I don't know the XI. But I'd have thought he's definitely up for selection, and would have thought he'll play."
Watch the Ashes live on Sky Sports this winter, beginning with the opening Test at the Gabba. Coverage begins at 11pm on Sky Sports 2 HD on 20 November.