Both second rows have put pen to paper on two-year deals that will see them play at the Sportsground until at least the summer of 2017.
Quinn Roux arrived at Connacht during the summer on an initial four-month loan deal from Leinster Rugby where he had played for two seasons having joined from Western Province in 2012. The loan deal with Connacht was recently extended to the end of the current season and Roux has now signed a new two-year contract to remain in Galway.
At Connacht, the 6ft 6ins, 19 stone South African has played in 14 games, starting in all but one, and has been instrumental in the province's drive for a top six finish.
Following three years in the Connacht Academy, 21-year-old Ultan Dillane, who made his professional debut this season, will progress to a senior contract. French-born Dillane moved to his mother's native Kerry when he was seven years old. He played his club rugby with Tralee RFC before attracting the attention of Connacht Academy Manager Nigel Carolan.
Dillane represented Ireland at both under-18 and under-19 level. Standing at 6ft 6ins and almost 17 stone, his ball carrying, imposing physicality, and threat at the set piece are just some of his major attributes.
Commenting on the news, Connacht Rugby CEO Willie Ruane said:
"We're delighted to have secured the services of both Quinn and Ultan for the coming seasons. Quinn is an example of a successful loan deal that worked for all parties concerned at the time and that has worked out very well. Everyone can see the contribution from Quinn on the pitch. He is a great fit for Connacht and we're delighted that he sees his future here with us.
"A huge part of our vision at Connacht is to build our squad depth as much as we can through our own systems and structures and Ultan coming through the Academy to a senior contract is an example of that.
"At this time of year, there are a number of talks ongoing with players and we hope to have more news on extended contracts in the coming days and weeks."
Head Coach Pat Lam added:
"As a coaching team, we are very excited to have both Quinn and Ultan staying with Connacht for at least the next two years. They are both young, abrasive locks who have real physical presence. I believe with continued game time and exposure at this level, they have the potential to play for Ireland in the near future.
"Quinn is someone who has impressed us all massively since he came in during the summer. His work ethic and desire to succeed on and off the field was apparent from day one. He has fit in extremely well with the rest of the squad and I know our supporters have really embraced him as well.
"It's a very important part of our vision and succession planning to have players coming through from the Academy. Ultan is someone we have watched develop under the guidance of Nigel (Carolan) and Jimmy (Duffy). He seized his opportunity last month and displayed in all three inter pro games the talent he has. We're delighted that he will be stepping up to the senior squad next year."
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