Northampton Saints could face a fine for allowing George North to play for Wales in this weekend's match against Australia.
North has a clause in his Saints contract which allows him to play in all Wales Test matches, but Saturday's game falls outside the official window for autumn internationals.
Premiership Rugby will now investigate Northampton's decision to release him.
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It will be a cold and clear night with a widespread frost away from the coast as temperatures dip to -2 deg C.
Saints now a point clear at the top after beating Harlequins
A cold day with some icy stretches, especially in the morning. It should stay dry with some good sunny spells.