Paris Saint-Germain have had an extraordinary window.The French giants have already completed the signings of Sergio Ramos, Gianluigi Donnarumma and Georginio Wijnaldum, all on free transfers.They also signed Achraf Hakimi in a €70 million move from Inter Milan.Mauricio Pochettino's side are now expected to sign Lionel Messi after his contract with Barcelona expired.Multiple outlets have reported that Messi has agreed to join PSG.It is unknown when he will arrive in the French capital, though. Journalist Fabrizio Romano reported on Sunday evening that Messi has not booked a flight yet.ENTER GIVEAWAYHowever, despite not knowing when exactly he will arrive, that has not stopped PSG fans causing carnage outside Paris' Le Bourget airport.Videos have emerged on social media of PSG fans in their droves waiting outside an exit of the airport.Fans can be seen holding flares and screaming Messi's name.The scenes looked chaotic. You can check out some videos below:

We get the impression that PSG fans are rather excited that Messi is set to join the club.

While Messi is expected to join PSG, the 34-year-old was coy when asked about the links in his press conference on Sunday.

"It is a possibility [that I join PSG], but I have not agreed anything with anyone," he said, per BBC.

"I have got different clubs interested. Nothing is definitive but clearly we are talking to them."

If he joins PSG, they will be able to field a front three of Kylian Mbappe, Neymar and Messi.

Lionel Messi signs for PSG | The Football Terrace

They would also boast world-class talent in other areas of the pitch, including Marco Verratti in midfield and Sergio Ramos in defence.

PSG will undoubtedly be the overwhelming favourites to win the Champions League should the deal be completed.