The 34-year-old enjoyed a fruitful year at club level, scoring 32 times in 40 appearances across all competitions for PSG and Barcelona, but it was his exploits with Argentina that were most impressive, claiming the first major international trophy of his career by winning the Copa America.
Bayern Munich's prolific striker Robert Lewandowski came second to Messi, but became the first winner of the Striker of the Year award after outscoring every player in Europe's top five leagues, netting 53 times in 42 appearances across all competitions so far in 2021, averaging a goal every 67 minutes.
Messi's PSG team-mate Gianluigi Donnarumma claimed the Yashin Trophy, awarded to the best goalkeeper, and was named 10th in the Ballon d'Or voting.
Donnarumma starred for Italy as they won Euro 2020, making a number of crucial saves in the shoot-out victory over England in the final.
Barcelona and Spain youngster Pedri won the Kopa Trophy after featuring heavily for club and country despite only turning 19 on November 25, also being shortlisted for the Ballon d'Or and finishing 24th.
Another Barca midfielder, Alexia Putellas, picked up the women's top prize, having helped the Catalan giants' women's team to Champions League and domestic glory in 2020-21.
Finally, Chelsea had 11 players nominated across all categories, making them the inaugural Club of the Year winners.
Award winners in full:
Men's Ballon d'Or – Lionel Messi (PSG and Argentina)
Kopa Trophy – Pedri (Barcelona and Spain)
Yashin Trophy – Gianluigi Donnarumma (PSG and Italy)
Club of the Year – Chelsea (England)
Striker of the Year – Robert Lewandowski (Bayern Munich and Poland)
Women's Ballon d'Or – Alexia Putellas (Barcelona and Spain)
The 23-year-old ended last season on the high of a Euro 2020 triumph with the Azzurri, shortly before a move to Paris Saint-Germain alongside fellow new recruits Lionel Messi and Sergio Ramos.
But fast-forward nine months, and he has struggled with costly performances for club and country, resulting in Italy's failure to reach the World Cup and PSG's Champions League exit.
Ex-Selecao goalkeeper Julio Cesar feels Donnarumma has possibly struggled with expectations since his arrival at the Parc des Princes.
"Being a keeper is tough," he told Stats Perform courtesy of Enterprise Rent-A-Car. "Donnarumma made his debut at AC Milan when he was 16, then he joined the national team.
"He has already won a European Championship at such a young age, and then to join one of the strongest teams in the world, which is full of champions.
"Many positive things happened to this young man, sometimes it is not easy to have that personality you need to get on the pitch after all the things he has been through down the years.
"From being the strongest keeper of the world, to become the player making the mistake that kicked PSG out of the Champions League.
"Everybody was expecting PSG to reach the final simply because the club brought [Sergio] Ramos, [Achraf] Hakimi, [Lionel] Messi and him [Donnarumma]."
Donnarumma may not have been solely at fault for Italy's World Cup play-off exit to North Macedonia or PSG's elimination at the hands of Real Madrid, but Julio Cesar believes the ex-Milan star needs to learn to maintain his level amid the peaks and troughs of the game to become one of the best in the business.
"In football there are ups and downs, but you need to be consistent if you want to become a great keeper," he added. "If you make a mistake during a match, you cannot miss the next 10 or 20 balls.
"Otherwise, you are out. This is what I think, however, the team did not help. I am talking about both club and national team.
"PSG did not do a nice game against Real Madrid, same for Italy when they had the chance to qualify for the World Cup.
"He is a lad who still has a lot to give to football, he can offer a lot to this sport. He is very young, and fans will be happy to watch him playing, because he is a young talent."
Liverpool goalkeeper Alisson and full-back Trent Alexander-Arnold are also included, although there is no place for Mohamed Salah.
PSG's attacking trio of Lionel Messi, Neymar and Kylian Mbappe are among the forwards, as is Manchester United star Cristiano Ronaldo.
Veteran Dani Alves also won enough votes to make the list, even though the 38-year-old, who recently rejoined Barcelona, only played 16 times in domestic competition in Brazil this year.
Professional footballers across the world were asked to vote for the three players they considered to have the best seasons during the 2020-21 season among goalkeepers, defenders, midfielders and forwards.
FIFPRO said: "For the first time in 17 years, FIFPRO is updating the announcement about the most-voted players, reducing the shortlist from 55 to 23. This has been done to resemble a real-life 'squad' which, usually for international competitions, is the number of players involved.
"The three goalkeepers, six defenders, six midfielders and six forwards with the most votes earned a place in the 23-men World 11 'squad'. To complete this elite selection, the two remaining outfield players with the most votes were added."
The keeper, three defenders, three midfielders and three forwards with the most votes will be chosen for the World 11, with the remaining spot assigned to the outfield player with the next highest number of votes.
The final 11 will be announced at The Best FIFA Football Awards ceremony on January 17.
FIFA FIFPRO MEN'S WORLD 11 23-PLAYER SHORTLIST:
Goalkeepers:
Alisson (Liverpool, Brazil)
Gianluigi Donnarumma (Milan/Paris Saint-Germain, Italy)
Edouard Mendy (Chelsea, Senegal)
Defenders:
David Alaba (Bayern Munich/Real Madrid, Austria)
Jordi Alba (Barcelona, Spain)
Trent Alexander-Arnold (Liverpool, England)
Dani Alves (Sao Paulo/Barcelona, Brazil)
Leonardo Bonucci (Juventus, Italy)
Ruben Dias (Manchester City, Portugal)
Midfielders:
Sergio Busquets (Barcelona, Spain)
Kevin De Bruyne (Manchester City, Belgium)
Bruno Fernandes (Manchester United, Portugal)
Frenkie de Jong (Barcelona, The Netherlands)
Jorginho (Chelsea, Italy)
N'Golo Kante (Chelsea, France)
Forwards:
Karim Benzema (Real Madrid, France)
Cristiano Ronaldo (Juventus/Manchester United, Portugal)
Erling Haaland (Borussia Dortmund, Norway)
Robert Lewandowski (Bayern Munich, Poland)
Romelu Lukaku (Inter/Chelsea, Belgium)
Kylian Mbappe (Paris Saint-Germain, France)
Lionel Messi (Barcelona/Paris Saint-Germain, Argentina)
Neymar (Paris Saint-Germain, Brazil)
Goals from Giacomo Raspadori and Federico Dimarco saw the Azzurri leapfrog their hosts to top Group A3 and qualify for next year's finals, alongside Croatia and the Netherlands.
Yet the visitors were forced to weather a late onslaught from Hungary, kept in the game through Paris Saint-Germain keeper Donnarumma, who lived up to his reputation with a string of impressive saves.
That gradually eroded control over the match frustrated Mancini, who felt his side rested on their laurels too much across the closing stages of Monday's encounter.
"It was a difficult game," he told RAI Sport. "It was all perfect until the final 20 minutes.
"We really need to improve in our ability to control the game for 90 minutes, as we worked so hard to be 2-0 up, so suffering like that in the final 20 minutes just makes no sense.
"We should have kept pushing for a third goal. I lost my voice because I was shouting so much in the final 20 minutes."
Rossi, who played alongside Mancini in a brief stint with Sampdoria almost three decades ago and embraced warmly at full-time, was more philosophical on his side's defeat.
However, the Italian was fast to praise countryman Donnarumma, who after something of a mixed first year at PSG following his Euro 2020 heroics, looks back to his best this season.
"It would have been nice to perform a miracle tonight, but when you play against teams like Italy, you have to make zero mistakes and hope the other side get it wrong," Rossi said in his post-match press conference.
"Even when we did have the chances, we were kept out by the best goalkeeper in the world. It's no coincidence that PSG signed Donnarumma."
Rossi also hailed Hungary's supporters, praising their "great respect and civility" for their opponents in Budapest.
"I've been in football for many years," he added. "I've seen packed stadiums and fans on their feet, but never anything like the passion you can feel when Hungary play on home turf."
The Genoa forward’s double separated the teams, after Darwin Machis equalised for the South Americans on the night in Fort Lauderdale.
The Euro 2020 champions relied on Paris St Germain goalkeeper Gianluigi Donnarumma once again and his penalty saving heroics were on full display.
The penalty came early. Italy’s blushes were saved through Donnarumma who got down smartly to deny Salomon Rondon’s spot-kick in the opening minutes.
Italy enjoyed long spells of possession and Federico Chiesa went close to opening the scoring.
The Juventus winger cut inside on the left, opting for the far post but his whipped effort missed the target.
Machis was Venezuela’s brightest player up to this point. He delivered an inch-perfect ball to the head of Rondon but the former West Brom and Everton player’s header failed to trouble Donnarumma.
Italy broke the deadlock in the 40th minute. Goalkeeper Rafael Romo’s poor clearance was picked out by Andrea Cambiaso who laid the ball off to Retegui and the forward smashed the ball in from close range.
Italy’s lead only lasted a few minutes as the potent Machis levelled proceedings.
Donnarumma’s poor pass put Giacomo Bonaventura under pressure and Machis’ pressing forced the mistake out of the midfielder before he provided a composed finish.
The Azzurri were left frustrated and they missed an opportunity to go ahead on the hour when Alessandro Buongiorno should have done better with a header which sailed over the crossbar from a free-kick.
Retegui then capped an impressive night with the winning goal 10 minutes from time.
Jorginho used good footwork to beat a defender after a poor clearance and the Arsenal midfielder laid the ball off to the clinical Retegui, who completed his brace with a powerful finish.
