London Irish have agreed a deal to sign Ulster fly-half Ian Humphreys, while stalwart Kieran Roche will retire at the end of the season.
Humphreys, 30, still has a year to run on his Ulster contract, but he will now join the Exiles this summer.
The former Leicester Tigers man, who failed to make the Ulster line-up for the Heineken Cup semi-final win over Edinburgh last weekend, has struggled for consistency this season.
He will be vying with Shane Geraghty - who arrives from Brive at the end of the campaign - for a place in London Irish's starting XV.
Humphreys expressed his excited at the move to the Premiership club, stating: "I am very excited to be joining London Irish.
"They play an attractive style of rugby that I am looking forward to being involved in. My immediate focus, however, is with Ulster as we prepare for the Heineken Cup final."
Ulster head coach Brian McLaughlin paid tribute to Humphreys.
"Ian has been an excellent servant since he returned to play in the province four years ago, and his performances have contributed to Ulster enjoying one of the most successful periods in their recent history," McLaughlin said.
"The squad depth has improved considerably in the time that Ian has been with us, and we are fortunate to have a number of contenders for the number 10 shirt.
"Paddy Jackson is a prodigious talent who has played very well this season, while Stuart Olding and Ruan Pienaar are also options for us.
"I am keen to stress that the job is not yet finished for Ian, and he is still very much in contention to play in the Heineken Cup final.
"There would be no better way for Ian to finish his Ulster career than with a Heineken Cup winner's medal."
Meanwhile, Roche has confirmed he will be retiring from the game after 14 years as a professional.
Roche's final game for the club is this weekend's home clash against Gloucester and he is hoping to finish on a winning note.
"I would like to thank everyone who has played a part in my rugby career, from my school days onwards, including the players, coaches and support staff that I have worked alongside both at Saracens and London Irish," he told the club's official website.
"I'm looking forward to taking to the field one last time for London Irish at Madejski Stadium this weekend alongside some of those friends and hoping for a victorious send-off for everyone who is moving on."