England prop Joe Marler could face punishment from the Rugby Football Union after an obscene remark directed at former Australia coach Bob Dwyer was posted on his Twitter account.
Dwyer claimed Dan Cole scrummaged illegally during England’s victory over the Wallabies on Saturday.
The RFU has strict guidelines on the use of social media.
Marler, 25, was fined £20,000 and given a two-week ban in April for calling Wales prop Samson Lee “Gypsy boy”.
He was suspended for a further two weeks for kicking Grenoble hooker Arnaud Heguy in his first game back.
Marler subsequently made himself unavailable for England’s tour of Australia, saying he was “not 100%”.
The Harlequins forward was accused by Dwyer of scrummaging illegally during the build-up to England’s World Cup group game against Australia last year.
The offensive tweet was quickly deleted from his account.
Eddie Jones’ side will seal England’s first series win in Australia if they win the second Test in Melbourne on Saturday.
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