And just like that, the balance of power in world football shifted to Paris.

Lionel Messi was officially unveiled Tuesday by Paris Saint-Germain, signing as a free agent after a whirlwind week in which the Argentine megastar ended his superlative 21-year affiliation with Barcelona.

Messi inked a two-year contract with the Ligue 1 outfit. The deal includes an option for a third season.

The 34-year-old was in tears Sunday as he bid farewell to the only club he’s ever known as a professional. The mood was much more jovial Tuesday, though, as he posed with the No. 30 PSG kit – a sight, and a shirt number, that will take some getting used to.

Prior to his unveiling, a smiling Messi greeted hundreds of joyous PSG supporters who gathered to welcome the star forward and his family to the French capital after his flight from Spain.

He will link up with former Barcelona teammate – and close friend – Neymar and French superstar Kylian Mbappe at the Parc des Princes, forming what could be the most dominant attacking triumvirate in football history.

Messi was offered the No. 10 shirt by Neymar, ESPN reports, but turned it down, opting instead to return to the number he wore in his debut season with Barcelona.

“I am excited to begin a new chapter of my career at Paris Saint-Germain,” the six-time Ballon d’Or winner said.

“Everything about the club matches my football ambitions. I know how talented the squad and the coaching staff are here. I am determined to help build something special for the club and the fans, and I am looking forward to stepping out onto the pitch at the Parc des Princes.”

Messi was a free agent after his contract with Barcelona expired on June 30. He was expected to remain with the Catalan club after agreeing to reduce his salary and sign a new deal, but Barca announced last week they could not register the contract with La Liga due to financial constraints.

He had been with the club since 2000, scoring 672 goals in 778 appearances and lifting 34 trophies.

The decorated attacker said Sunday that he wanted to stay at the Camp Nou, but when it became clear that was no longer possible, PSG moved quickly to secure arguably the most coveted signature in the sport.

“I am delighted that Lionel Messi has chosen to join Paris Saint-Germain and we are proud to welcome him and his family to Paris,” club chairman Nasser Al-Khelaifi said. “He has made no secret of his desire to continue competing at the very highest level and winning trophies, and naturally our ambition as a club is to do the same. The addition of Leo to our world class squad continues a very strategic and successful transfer window for the club.”

PSG, desperate to hoist the Champions League trophy after years of heavy transfer expenditure, already added Gianluigi Donnarumma, Sergio Ramos, Georginio Wijnaldum, and Achraf Hakimi to the squad this summer prior to the stunning acquisition of Messi.