AUSTRALIA lock Rory Arnold has been slapped with a three-week ban, ruling him out of contention for the first Test against Ireland in Brisbane on June 9.

His suspension came after he received a red card during the ACT Brumbies' 42-24 loss to the Golden Lions in their Super Rugby match in Johannesburg on Sunday.

Arnold, who had been yellow-carded earlier in the game, was sent off for shoulder charging Lions flyhalf Elton Jantjies, striking the South African in the jaw.

Super Rugby organisers SANZAAR said in a statement that Arnold's excellent disciplinary record plus his remorse and guilty plea reduced a potential six-week ban to three.

The dismissal had a crucial bearing on the Super Rugby game as Brumbies saw a three-point lead overturned soon after.

Australia host Six Nations champions Ireland on three consecutive Saturdays from June 9 in Brisbane, Melbourne and Sydney.