Nigel Owens was forced to leave the field injured just days before he is due to fly out to Japan for the Rugby World Cup.
Owens limped off at the Arms Park 63 minutes into Friday night's Indigo Premiership opener between Cardiff RFC and Pontypridd - his final match before the World Cup.
He was replaced by Gwyn Morris after suffering a suspected dead leg.
The Welsh ref is due to arrive in Japan next week and begin preparations for the opening match between Japan and Russia on September 20, which he has been chosen to officiate.
Following the incident, Owens said on the BBC's live coverage of the game: “A player got tackled and fell into me and I think I got a dead leg. I don't think I've got anything too bad. It was a precautionary to come off."
Earlier this week it was announced Owens will take charge of a Wales international for the firs time later this year after World Rugby granted him special dispensation to referee Wales v Barbarians. You can read the full details on that development here.
Cardiff came from behind to win Friday's match 24-23 with a last minute touchline conversion.
