Andy Farrell, the Saracens and England player and former Great Britain rugby league captain, is to retire from professional rugby at the end of this season.
The former Wigan Warriors talisman switched codes in 2005, joining Saracens and going on to win eight caps for England, including being part of their 2007 World Cup squad.
He will remain at Sarries, taking up a role as skills coach with the Guinness Premiership club.
Farrell, 34 next month, enjoyed an 18-year playing career across both rugby codes.
He said: "My mind still feels as sharp as ever, but my body is telling me different things.
"Throughout my career I've always prided myself on doing extra training to stay one step ahead of opponents, but I'm now finding myself spending all my time just trying to get right for training, rather than trying to be a better player.
"When that time comes, it is time to stop."After 18 years, it will be an emotional moment to play my last game, but I'm really excited about the opportunity that Saracens have given to me to move into coaching - something I have always wanted to do.
"I've always been interested in coaching, and I've been lucky enough to work with some fantastic people during my career and I'm looking forward to putting into practice all the knowledge I've gained over the years.
"Farrell made his second team debut for Wigan aged just 15, and within a year he had become a first team regular.
He made his Great Britain debut aged 18, and at 21 he became the youngest captain of his country, going on to make 34 GB appearances.
During his time at Wigan, Farrell won five championships and four Challenge Cups, then joined Saracens in a deal that was part-funded by the Rugby Football Union.
His early union career was hit by injuries - and an initial debate about whether he should play centre or flanker - but he soon settled into a midfield role and made his England debut against Scotland in 2007.
Farrell's final Test match appearance was as a replacement against Tonga during the 2007 World Cup pool game in Paris.
He added: "I had 14 great years with Wigan and have so many people to thank at the club over the years for all the help and support they gave me.
"I've also met some special people at Saracens and was also fortunate enough to become a dual international and represent England at a World Cup.
"The fans of both clubs have given me tremendous support, and I'd like to thank them for that. I've no regrets looking back, and I've been fortunate enough to play with and against some fantastic people and have some fantastic experiences.
"But my time as a player is not over yet.
"There is still a huge amount to play for with Saracens, and we have a big game on Sunday against Newcastle in the European Challenge Cup.
"I would love to sign off on a high note, and winning a trophy would be just that."
England's preparations for the Autumn International series were potentially dealt a further blow as Maro Itoje was forced to undergo an x-ray after Saracens' European victory over Scarlets on Saturday night.