Gloucester have appointed George Skivington as their new head coach, to replace the departed Johan Ackermann.
Skivington, 37, arrives at Kingsholm from his role as forwards coach at fellow Premiership side London Irish.
Ackermann, 50, ended his three-year stay at Gloucester last month to move to Japanese side NTT Docomo Red Hurricanes, who are based in Osaka.
"I've had a look at the playing squad, and there are some really great players in there," said Skivington.
"When I was playing, Gloucester was one of a couple of clubs that you never fancied visiting. We want to bring that feeling back to Kingsholm."
However, London Irish chief executive Brian Facer says that the club will reserve the right to consider all its options after the announcement.
London Irish say Skivington is still under contract with the club until June next year and there has been no formal or informal approach from Gloucester asking permission to talk to the former England Saxon.
"To say we are disappointed with Gloucester's announcement is an understatement," Facer said in a statement on Saturday.
"George is well liked and respected at Hazelwood, and it is understandable that we would not want to lose him, especially so close to the resumption of play after the lockdown. We also know that he is an ambitious young man who would relish the opportunity of being the head coach of a club some day.
"However, the protocols are clear that a club must be approached in writing when there are more than six months remaining on the relevant contract, regardless of whether it is a player or coach.
"George is under contract with London Irish until June 2021 and has not served us with the required notice period, nor have the terms of his contract been breached. More importantly, at no point have we received any proactive communication whatsoever from Gloucester.
"We therefore believe that Gloucester have breached the Premiership Rugby Code of Conduct regarding inducement and approaches to a contracted player, member of coaching staff and other contracted person.
"This is a most serious issue so, accordingly, we are reserving our rights to consider all our options under the Premiership Rugby governance protocols and other avenues of redress."
Gloucester and England fly-half Danny Cipriani described the news as the "most exciting announcement of a head coach I've seen in rugby".
He posted on Twitter: "The type of man you build a club around. Very grateful I'll get to play out my last years under him."
But chief executive Lance Bradley said Skivington, who will start his new role on 3 July, was the Cherry and Whites' "clear first choice".
"George has a great reputation within the game, and is one of the new generation of highly talented young English coaches," said Bradley.
"He has signed a long-term contract and we look forward to working with him to deliver the vision we have for our club."
Gloucester have also promoted commercial director Alex Brown to chief operating officer.
His role will include recruitment after the club decided not to replace the director of rugby position when David Humphreys, 48, leaves at the end of June after six years in charge.
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