Israel Fulau was injured during his test return as Tonga lost 36-0 to Fiji in the Pacific Nations Cup.
The 33-year-old Christian fundamentalist has 73 caps for Australia but has also made his debut Contract terminated in 2019 after posting an anti-gay tweet.
change in Rugby world rules Last year he was allowed to switch allegiance to Tonga.
Fulau injured his leg in a crash when chasing a kick and knocked out in the 27th minute against Fiji.
He was listed as ‘Isileli Folau’ by Tonga and named on the right wing of the match in Suva.
He only had two ineffective touches before being substituted and it is unclear whether he will be fit for Tonga’s remaining matches in the four-nation tournament.
In the previous match, Samoa managed a dramatic 31-26 victory over Australia A.