Cape Town - Springbok lock Franco Mostert made his debut for Gloucester on Saturday, but the Lions are reportedly still seeking intervention from World Rugby in relation to how the deal was done for the player to join the English club.
The Lions feel that there were irregularities in Gloucester's negotiations with Mostert, who came on in the 71st minute of his new club's 36-16 win over Worcester Warriors.
According to Afrikaans newspaper Rapport, the Lions have sent a strong request to World Rugby to reconsider their decision to clear Mostert to play after having ruled that there was nothing illegal in the negotiation process.
Gloucester coach Johan Ackermann, meanwhile, hit back at his former employers in Johannesburg.
"I’m surprised that they did it because why didn’t they do the fight for Jaco Kriel and Ruan Dreyer or Faf de Klerk or any other player that left them in the last two seasons?" Ackermann was quoted as saying on Gloucestershire Live.
“I’m surprised more because I thought every player and every person has got free will to choose where he wants to go so.
"If I sign a contract and it ends on a certain date or time, surely I can make a decision on my future forward.
"Regardless of when that contract was decided, the view is that person made a conscious decision, my next chapter in my life is with X, Y and Z."
Gloucester are next in action when they take on the Exeter Chiefs, away, in a European Champions Cup clash on Saturday.