Manchester United have reached an agreement with Juventus to re-sign forward Cristiano Ronaldo.
United will pay Juventus an initial €15m (£12.86m) plus a potential €8m (£6.86m) in add-ons for the Portugal captain, who is expected to undergo a medical in Lisbon and sign a two-year contract this weekend.
On Friday afternoon, Ronaldo's agent Jorge Mendes said the 36-year-old's return to United was very close to being agreed and the club officially announced the news shortly before 5pm.
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"Manchester United is delighted to confirm that the club has reached agreement with Juventus for the transfer of Cristiano Ronaldo, subject to agreement of personal terms, visa and medical," a United statement read.
"Everyone at the club looks forward to welcoming Cristiano back to Manchester."
Ronaldo has entered the final year of his £500,000-per-week Juventus contract and told boss Massimiliano Allegri he has "no intention" of representing the club again.
United's Premier League rivals Manchester City were in talks to sign Ronaldo but later pulled out of a potential deal.
Ronaldo spent an hour and a half at Juventus' training ground on Friday morning to say goodbye to his team-mates before boarding a private jet from Turin to Lisbon.
In a farewell post on social media, Ronaldo wrote: "Today I depart from an amazing club, the biggest in Italy and surely one of the biggest in all of Europe. I gave my heart and soul for Juventus and I'll always love the city of Turin until my final days.
"The 'tiffosi bianconeri' always respected me and I tried to thank that respect by fighting for them in every game, every season, every competition. In the end, we can all look back and realize that we achieved great things, not all that we wanted, but still, we wrote a pretty beautiful story together.
"I will always be one of you. You are now part of my history, as I feel that I'm part of yours. Italy, Juve, Turin, tiffosi bianconeri, you'll always be in my heart."
Ole: Ronaldo knows we are here
Ronaldo, a five-time Ballon d'Or winner, scored 118 goals in 292 appearances for United between 2003 and 2009 under former boss Sir Alex Ferguson.
He won three Premier League titles, the FA Cup, two League Cups and the Champions League before leaving for Real Madrid in a then world-record deal.
Speaking on Friday before news of Ronaldo's return was confirmed, current United manager Ole Gunnar Solskjaer said: "I didn't think Cristiano was going to leave Juventus. It has been speculation this morning and the last few days of course.
"We have always had good communication. I know Bruno [Fernandes] has been talking to him as well. He knows what we feel about him and if he was ever going to move away from Juventus he knows we are here."
Ronaldo has scored 783 goals for club and country, winning over 30 trophies including seven league titles, five Champions Leagues, and the European Championship.
Solskjaer, who played alongside Ronaldo during the latter stages of his career at United, described his former team-mate as a "legend" of the club and the "greatest player of all time".
"I was fortunate enough to play with him, I coached him when I got my job (as manager of United's reserve team)," the Norwegian added.
"Such a tremendous human being so let's see what happens with Cristiano. Everyone who has played with him I think has a soft spot for him."
Gary Neville says the return of Ronaldo to United will give supporters hope of a great season ahead.
"It's fantastic news," Neville told Sky Sports News. "It's a little bit nostalgic, which doesn't always work in football, but the idea of Ronaldo going to Manchester City was torture for United fans.
"If there is a big player available, United have to be in the market. We know there's a potential that Erling Haaland could be available next summer, Edinson Cavani's probably got a year, they definitely need a forward option with Cavani.
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"I know they've got Mason Greenwood but if you look at the business Chelsea have done, that Manchester City were looking to do, Manchester United had to compete, and what they've done is bolster the squad with a proven goalscorer, a club legend, and it's going to give them an incredible 12 months.
"Ronaldo will be coming to win trophies, personal accolades, set the Premier League on fire. It is a different Ronaldo, everyone expected that.
"But he is a No 9, someone who still has that burst over short distances, he makes great runs inside the box, has anticipation of where the ball's going to drop, and he gives United something they need.
"I said the other day United should be in for Harry Kane if he was available, or Haaland. These types of players. To get above Manchester City and Chelsea they're going to have to do something big, and this could give them a temporary shot in the arm to get them right up there this year.
"I was a little bit fearful watching Chelsea last weekend, knowing City are going to be strong, Liverpool have Virgil van Dijk back, that United could improve but finish in a lower position. But this news gives me more hope that they can have a great season.
"This is one of the most special players that has ever lived, forget Manchester United, it's one of the greats of all time."
How a 'whirlwind 24 hours' led to Ronaldo's return
Sky Sports News' Dharmesh Sheth on the Transfer Show:
"The past 24 hours have been a whirlwind. I was checking my texts and one I got at 3.44pm yesterday, I got a text saying City was the most likely destination, as recently as that.
"We knew yesterday that Jorge Mendes was speaking to the biggest clubs in European football, but weren't getting any confirmation from United that they had been approached.
"They were satisfied with the business they had done, I was told even two weeks ago the bulk of their business had been done, and they had filled their priority positions. The feeling was that he was going to City - up until Solskjaer's news conference earlier on today.
"His body language gave it away for one, as well as what he said. Simply because when he was asked about Ronaldo, we were expecting him to straight bat it away, but that didn't happen.
"For him to come out and say that in a news conference was incredible, and we were thinking this is on, suddenly! Then it emerged Mendes had approached United about a deal, and the speed at which it has accelerated has even surprised me.
"We went from that to advanced talks to Mendes giving United the thumbs up, to United announcing it."
Sky Sports' Nick Wright:
All the twists and turns of a summer-long transfer saga condensed into the space of a few days. Cristiano Ronaldo seemed destined for the Etihad Stadium but now an even more remarkable story is unfolding as he returns to Manchester United.
It is 12 years since his departure. Twelve years during which he has scored 551 goals in 572 appearances for Real Madrid and Juventus, adding four more Champions Leagues to the one he claimed with Manchester United and a whole lot more besides.
His return is a thrilling and emotive prospect for supporters. Ronaldo is still adored at Old Trafford, his name still sung in the terraces and his achievements still a source of considerable pride.
But will his extraordinary, trophy-hoarding success continue under his former team-mate Ole Gunnar Solskjaer? And what kind of player are United getting all these years later?
Rio: Sir Alex key to Ronaldo's return
Rio Ferdinand believes Ronaldo's return to Manchester United is largely down to a helping hand from Sir Alex Ferguson.
Speaking on his YouTube channel, former United defender Ferdinand said: "Cristiano and Sir Alex Ferguson have got a bond.
"Very few players get to have that in their career with a manager. Sir Alex played a massive part.
"There was no way Cristiano was coming to Man Utd without speaking to Sir Alex. Simple as that."
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