Richard Wigglesworth has been named as Leicester Tigers' interim head coach, retiring as a player to replace Steve Borthwick after his England departure.
Wigglesworth hangs up his boots at the age of 39, having made an all-time record 322 Premiership appearances during his 20-year career.
The scrum-half was already working as a coach at Tigers when he helped them to the Premiership title in June.
"It's a bittersweet day," Wigglesworth told the club website.
"The decision to retire from playing was not easy. I have given absolutely everything to my playing career and loved every minute of being a professional rugby player.
"I would not have taken on the head coach role of Leicester Tigers if I did not believe there was a group of players and coaches who are committed to being successful and, with those at this club, that cannot be questioned."
Wigglesworth - a three-time European Champions Cup winner - became the oldest player to win a Premiership title when he started in the victory against former club Saracens in June to claim a record seventh crown.
The former England scrum-half was first appointed to Leicester's coaching team in September 2021, and it was a role he had appeared set to continue in this season after signing his latest contract in May.
Eddie Jones' departure as England boss earlier in December, however, eventually led to Borthwick's departure for the national team.
Defence coach Kevin Sinfield has also left Tigers to continue to work with Borthwick in the England job.
"I am grateful to Steve and Kev for what they have taught me, how they have challenged me and the friendship I have with both," Wigglesworth said.
"Myself and Leicester Tigers are better for having worked with them."
Borthwick took a struggling Tigers side - one that was only spared the drop in 2020 after Sarries were relegated for salary cap breaches - and returned them to the Premiership summit with their first English title for nine years.
Leicester's chief executive Andrea Pinchen admitted "it was disappointing" to have Borthwick's departure confirmed, but said the club wanted to "celebrate what has been achieved" under the 43-year-old.