Confirmation of his retirement is not unexpected, but it is deeply unfortunate for a player who took the brave and unique move to go to New Zealand to get his professional career off the ground with Canterbury and Crusaders after a stint in the Leinster academy.

"I have a lot of admiration for how he earned his stripes as a rugby player, taking a chance as a teenager and moving across the world to New Zealand,” said McMillan.

"It's an amazing story really, how he earned a contract at one of the biggest club sides in the world at Crusaders and played such a key role in their success.

"He has made a big contribution to Munster Rugby as a player and a person, and is extremely highly-regarded by teammates, staff and supporters alike.

"It's every player's dream to represent their country and to have earned a cap with Ireland is something I'm sure he will look back on very fondly.

“I know he will enjoy great success with whatever he chooses to do next in life and we wish him and his family the very best."

Jager was also selected for the New Zealand Barbarians and New Zealand XV sides but injury ruled him out of the latter and left the door open to represent Ireland, which he ultimately did at ‘A’ and at Test level when appearing in the Six Nations against Wales.

That was in the spring of 2024, three months after he had made the switch from Crusaders to Munster, but his time with the province was pockmarked by injuries and he was limited to 35 appearances for the club in just less than three full seasons.

“It is with a very heavy heart that I share that I have been advised to medically retire from rugby,” Jager explained on Saturday. “Playing professional rugby for the last 10 years has been nothing short of a privilege.

“I am incredibly grateful to everyone who has been part of my journey — my coaches, teammates, medical and rugby staff, supporters, friends, and family. Each of you has helped shape me not only as a player, but as a person.

“While this chapter comes to an end, I look back with immense pride and gratitude for the experiences, memories, and relationships the game has given me. Who knows what the next chapter holds, but I’m excited to see what it has in store.” 

Born in London, Jager started out at Naas RFC before playing schools rugby at Newbridge College and Blackrock College. He lined out for the Ireland U18 Schools team in 2013 and also lined out for the Netherlands at U18 level before moving to New Zealand aged 17.

Initially attending the Crusaders International High Performance Unit, he earned a place in the Crusaders Academy in 2014.

After impressing with New Brighton RFC, he earned a place in the Canterbury squad for the Mitre 10 Cup in 2016 and won NPC titles in 2016 and 2017.

Jager made his Super Rugby debut for the Crusaders in 2017 and was a key member of their squad for seven years, winning seven consecutive Super Rugby titles.

He lined out for the Provincial Barbarians against the British and Irish Lions in 2017 and was twice selected for the All Blacks XV under McMillan.

His final game for Munster was against Ulster at Thomond Park in April.

Jager’s exit leaves Munster with more work to do in a front-row department that has been a concern for some time with reports that veteran tighthead and former England international Kieran Brookes is due to arrive from Perpignan.

Munster CEO Ian Flanagan had flagged a chase for All Black tighthead Tyrel Lomax last month only for the player to extend his contract with the Hurricanes and New Zealand rugby through to 2029 instead.

Flanagan has described the capture of a top tighthead as a “key focus” for the club.

John Ryan is retiring after 16 years of service while Roman Salanoa continues to endure injury torment with the Hawaiian stuck on just 30 caps since featuring off the bench in Munster’s URC Grand Final win three years ago.

Michael Alalatoa played 18 times, the vast majority as a starter, this season just ended while Conor Bartley and Ronan Foxe, the latter an academy man who has recently signed his first pro contract, are others further down the depth chart.