Michael Carrick is making an immediate switch from Manchester United's playing squad to the coaching team in time for Saturday's FA Cup final against Chelsea.
The former England midfielder hung up his boots on Sunday after United's final Premier League game of the season against Watford.
The following day he began his new job as a member of manager Jose Mourinho's coaching staff, with this weekend's clash against Chelsea at Wembley his first assignment.
"It changes overnight," Carrick said. "I am not training this week. I am going to jump on the staff."
The 36-year-old had other options as he approached the end of his playing career but the chance to work under Mourinho was too good to refuse.
"A couple of years ago I thought maybe it would be a good thing to spend time with the family, but then it's about timing and opportunities," said Carrick, who made 464 appearances for United over 12 years after earlier spells with West Ham and Tottenham.
"You never know what is going to be around the corner. As soon as this came up I didn't think twice.
"He is one of the best, he's been around for many years and it all fits in. I've been at this club, and it is such a great club, so I obviously know the club and the manager."
Carrick said he is considering moving into management one day but it is not something he intends to push for yet.
The midfielder was given a guard of honour by both teams on Sunday and had a hand in the only goal of the game, playing Juan Mata in behind the defence for the Spaniard to tee up Marcus Rashford.
He was substituted late in the game to a huge ovation, with supporters recognising his role in five Premier League title successes and one Champions League triumph.
Michael Carrick applauds the Old Trafford crowd at the end of the English Premier League match between Manchester United and Watford on May 13, 2018