Still suffering from the fractured left wrist he sustained in a heavy crash two weeks ago in Thailand, Lorenzo withdrew from this weekend's Japanese GP early in practice and also cast doubt on whether he could be fit for Australia.
Lorenzo suggested it would be "nearly impossible" to be fit for Phillip Island next weekend, given his wrist had failed to heal sufficiently in the two-week period between the Buriram race and Motegi.
On Sunday morning, Ducati announced Lorenzo will not travel to Australia and will instead return to his home in Barcelona with the objective of being ready to return for the Malaysian GP weekend on November 2-4.
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The team tweeted: "In accordance with the Ducati team, [Lorenzo] will return home today in order to have further checks with doctors and speed up the recovery of his left wrist.
"Jorge will miss the Australian GP next week and will try to be as fit as possible for the Malaysian GP."
Nieto Ducati rider Alvaro Bautista is the most likely candidate to replace Lorenzo at Phillip Island, as regular tester Michele Pirro is unavailable due to testing commitments at Valencia.
It is not yet clear who would replace Bautista at Nieto in this scenario.
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