Manchester United's Portugese manager Jose Mourinho says arrival of Pogba will signal the end of the club's spending spree.
French superstar Paul Pogba on Tuesday completed a sensational return to Manchester United from Juventus for a reported world record fee.
United said Pogba had signed a five-year contract but did not disclose the cost, while British media have put the transfer at 105 million euros, not including the agent's fee.
That would see the 23-year-old eclipse the 101 million euros Real Madrid paid Tottenham Hotspur for Gareth Bale in 2013.
"This is the right club for me to achieve everything I hope to in the game," said Pogba.
Pogba moved to Italy when United let him go for a nominal fee after his contract expired in 2012.
"I am delighted to rejoin United. It has always been a club with a special place in my heart and I am really looking forward to working with Jose Mourinho," added Pogba.
Pogba the key
United manager Mourinho has been tasked with bringing back the glory days to the 20-time English champions after three lean years since Alex Ferguson's retirement. And the former Chelsea boss believes Pogba can inspire United's revival.
"He has the chance to be at the heart of this club for the next decade and beyond," said Mourinho.
"Paul is one of the best players in the world and will be a key part of the United team I want to build here for the future. He is quick, strong, scores goals and reads the game better than many players much older than he is."
Pogba made just seven appearances during his previous spell at the club as a teenager, but returns as one of the world's most famous players after winning four consecutive Serie A titles and leading France to the Euro 2016 final.
Thanks @juventusfc and all Juventini. Goodbye means nothing, it is the time we spent together that matters— Paul Pogba (@paulpogba) August 8, 2016
"Thanks @juventusfc and all Juventini. Goodbye means nothing, it is the time we spent together that matters," Pogba posted on his official Twitter account.
It is the first time since now Real Madrid coach Zinedine Zidane joined the Spanish giants as a player from Juventus in 2000 that Madrid haven't got their hands on the world's most expensive player, having also bagged Cristiano Ronaldo from United in 2009 for a record fee.
United brought the long-running transfer saga to an end in the early hours of the morning UK time.
The reported fee does not include agent's fees. The transfer had stalled for weeks over how the two clubs would share the sizeable payout to Pogba's representative Mino Raiola.
And the huge cash outlay will lead to questions over how Ferguson allowed Pogba to slip out of United's hands four years ago over differences with Raiola.
In his 2015 book 'Leading', Ferguson described his first meeting with Raiola as "a fiasco".
"He and I were like oil and water," Ferguson wrote. "From then on, our goose was cooked because Raiola had been able to ingratiate himself with Paul and his family and the player signed with Juventus."
Raiola, who also represents two of United's other new signings, Armenian playmaker Henrikh Mkhitaryan and star Swedish striker Zlatan Ibrahimovic, is set to make millions from the deal.
Mourinho insisted United's financial muscle should be a source of pride not embarrassment.
"When other people break records, I don't think it's a reason to be sad. I think it's a reason to be proud with the dimension of a club that can do that and can attract players of this dimension."
However, the Portuguese boss has hinted Pogba's arrival will signal the end of United's spending spree.
"Our fundamental market is 75 percent done," he said during United's pre-season tour of China. "When we sign one midfield player that crucial work will be done."
Mourinho's reign got off to a successful start on Sunday as Ibrahimovic scored the winner in a 2-1 victory over Premier League champions Leicester City in the Community Shield.
Apart from Pogba's record fee, the other four highest transfer deals in the top five are:
Gareth Bale (WALES) Tottenham Hotspur to Real Madrid - 101 million euros - 2013
Welsh forward whose performances for an attractive Spurs side persuaded Real to bid for him. The English side could not refuse such advances and let their star man go.
He has built on his career at the Santiago Bernabeu with two Champions League titles, scoring in the final of the first of the two against Atletico Madrid. His experience in La Liga helped him lead Wales in their memorable run to the Euro 2016 semi-finals.
Bale also scored a stunning winner in the Copa del Rey final against Real's arch rivals Barcelona in 2014.
Cristiano Ronaldo (PORTUGAL) Manchester United to Real Madrid - 94 million euros - 2009
Real Madrid came calling for the Portuguese master with what was then a world-record bid.
Ronaldo was keen to join, and since arriving in the Spanish capital he has become their all-time top goalscorer and consistently set records in the Champions League, which he has won three times in his career, twice with Real.
He has achieved all this despite the hottest of competition from Barcelona's Argentinian superstar Lionel Messi, who still leads in the overall La Liga scoring charts.
Gonzalo Higuain (ARGENTINA) Napoli to Juventus - 90 million euros - 2016
Juventus paid the biggest fee for a domestic transfer in history when they matched Higuain's buy-out clause of 90 million euros to bring the Argentinian to Turin from Napoli last month.
The 28-year-old former Real Madrid striker was the top scorer in Serie A last season with a record-equalling 36 goals as Napoli finished second to Juve. Coach Massimiliano Allegri led Juventus to a record fifth consecutive league title in 2016, but he will be hoping that Higuain can help his side improve in Europe, after following up their 2015 Champions League final defeat to Barcelona with a last-16 exit at the hands of Bayern Munich.
Luis Suarez (URUGUAY) Liverpool to Barcelona £75m - 81 million euros - 2014
Barcelona didn't hesitate to sign the striker despite his shame at the World Cup finals when — for the third time — he bit an opponent, this time Italy defender Giorgio Chiellini.
As a result, Suarez was unable to play competitively or train with them for four months, but once his ban was over he repaid them in full.
No disgraceful incidents have followed and he ended his first season with them by scoring in the Champions League final win over Juventus.
His trident attacking partnership with Messi and Neymar yielded a La Liga record for three forwards of 122 goals that campaign.
He scored a hat-trick to seal the league title for Barca last term and went on to complete the domestic double in a season in which he grabbed a staggering 58 goals.