Australia’s emphatic victory levels the five-match series at 1-1 ahead of the next Test at Melboune which begins on Boxing Day.
The hosts needed only 50 minutes on the fourth day to take England’s remaining five wickets as Ryan Harris finished with a Test-best 6-47 with England all out for 123.
Strauss’s visitors resumed on 81-5, chasing an unlikely 391 to win in Perth, but Harris struck four times as England collapsed.
“It’s very disappointing defeat. No doubt about it,” said Strauss afterwards. “We came fully expecting to play the same brand of cricket that we played in Adelaide.
“We were in a great position after bowling them out for 268 and then being 70-odd for none in reply. The batting in both innings was sub-par.
“But we have to retain a sense of perspective. This result doesn’t make us a bad team overnight.”
The England captain added: “We need to retain the confidence we built from the first two Tests and come out all guns blazing in Melbourne.
“Now is not a time for panic. It is important to retain the method that’s worked well.”
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