Greig Laidlaw says he is standing down from international duty to give Scotland's next generation of scrum-halves the room to grow.
The former national team captain has confirmed his international retirement at the age of 34 following 76 caps.
The 39 times the Clermont veteran skippered the Scots is more than any other player, while Laidlaw also sits second on Scotland's list of their highest-ever point scorers with a tally of 714.
The former Edinburgh and Gloucester ace had already passed on the armband ahead of this year's World Cup – although he was back leading the team out against Japan after new captain Stuart McInally was dropped ahead of their fateful final pool game against the hosts.
He had managed to hold off the challenge of Glasgow pair Ali Price and George Horne for the number nine jersey but, while his leadership qualities and goal-kicking skills have never been in doubt, there have been critics who have questioned whether his pedestrian style of play is the right fit as Gregor Townsend strives to speed up Scotland's tempo.
And now, Laidlaw says, is the right time to make way.
"Emotionally, this decision was incredibly tough, however, when I reflected on what I have learned from playing Test level rugby and where Scotland is as a national team, it makes sense," said Laidlaw in a statement released by the Scotland Rugby Union.
"Captaining your country to victory is the stuff of childhood dreams. To say I will never again stand in the tunnel, filled with nerves, alongside my rugby family and lead my teammates out on to the pitch at Murrayfield, is incredibly hard.
"While my body and heart could continue playing, my head tells me that it's time to let the team rebuild.
"In terms of where Scotland is now, they are in a position to spring forward and I cannot wait to give them my full support from the stands.
"To the Scotland coaches and backroom staff over the years who dedicate hours behind the scenes to prepare the team collectively and as individuals, I thank you.
"To the people who have helped me achieve my dreams: my team-mates, my parents, sister, family, close friends and my incredible wife, Rachel, and our sons, I will be forever thankful for all the support you have shown me over the years; you have stuck by me through thick and thin.
"I'd also like to thank Scottish Rugby and the staff behind the scenes who have both supported me as captain and a player and enabled the team to perform in front of capacity crowds.
"And finally, a massive thanks to the Scotland supporters both in Scotland and abroad for sharing the rollercoaster ride of international rugby with me."
Laidlaw played three times at this year's World Cup, where Scotland failed to progress through to the knockout stage having led the team into the 2015 tournament.
He was also included in the British and Irish Lions squad for the tour to New Zealand in 2017, often captaining the midweek side.
But he now becomes the third Scot this month to announce he is retiring from international rugby following the decisions of flanker John Barclay, another former captain, and wing Tommy Seymour.
Townsend paid tribute to Laidlaw's dedication to the dark blue jersey.
"Greig has been an outstanding servant for Scottish rugby, through the passion and skill he displayed when wearing the thistle on his chest and also on the many occasions he led the side," Townsend said.
"That he began his Scotland career at stand-off before claiming the number nine jersey shows what an exceptional rugby player he is and was for Scotland and, to be captain on so many occasions, rightly places him alongside the best players to ever led the national team."
