Wallabies No 8 Wycliff Palu will play no further part in the Rugby Championship due to lingering concussion concerns.

The burly back-row forward sat out the narrow victory over Argentina at the weekend after failing to recover from the head knock he suffered in the win over the Springboks a week prior.

The Wallabies medical staff have decided to err on the side of caution, given his previous history, and advised that Palu take no part in the tour to South Africa and Argentina.

The injury comes as a further blow to the Wallabies' forward resources after Tatafu Polota-Nau was ruled out for the rest of the season with a high ankle sprain following Saturday's match.

Coach Ewen Mckenzie is set to announce a 28-man squad for the final two matches of the Rugby Championship on Wednesday.

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