The 24-year-old Sydney Roosters second rower missed the first Test win, but had hoped to play a part in the two remaining Tests.

But Morley's arm, broken while playing in Australia in July, had not healed sufficiently to allow him to feature in coach David Waite's plans.

"Combined expert medical opinion has said that he would be unfit for either the second or third Tests," said Clarke.

"It's a sad day for us all."

Injury also forced Morley to miss the 1997 Super League Test series against Australia and most of last year's World Cup campaign.

"It's an extremely serious blow," said Waite.

"He had come back from the injury and we believed the problem to be only slight.

"As it's turned out, over time it hasn't gone as well as we expected."

Great Britain play Australia in the second Test of the Ashes at Bolton's Reebok Stadium on 17 November.