Lionel Messi's time at Barcelona appears to be all but over.

After 16 years with the Catalan club, the Argentine is ready to try a new challenge and is reportedly eager to join forces with Pep Guardiola at Manchester City.

Messi's desire to leave stems from his lack of faith in the current sporting project at Barcelona under president Josep Maria Bartomeu.

The Blaugrana's failure to deliver the goods in the Champions League has been a source of huge concern for the world's best player.

Should Messi's desired exit be secured this summer it will continue a trend involving Barca's eternal enemy - Real Madrid.

Fans react to Messi wanting to leave

Los Blancos have won La Liga four times in the last 13 years and each time they have scooped Spain's biggest prize, Barcelona have had to say goodbye to a key name shortly after.

We'll run you through all four below.

2008: Ronaldinho's time at the club comes to an end

Real Madrid finished 18 points clear of Barca in 2007/08, spelling the end of the Frank Rjikaard era in Catalonia.

When Pep Guardiola was ushered in as the new manager, the Spaniard embarked on a 'cleanse' of the dressing room, one which saw the legendary Ronaldinho depart.

The Brazilian was still one of the world's best players at the time, but both him and Deco were thought to be bad influences on Messi and asked to leave.

It worked out pretty darn well in the end, but Ronaldinho's exit in particular was a painful one to take for the Barca faithful.

Ronaldinho with Barcelona

2012: The end of the golden era under Guardiola

As soon as Jose Mourinho's Real Madrid ended Barcelona's three-year reign as La Liga champions, Guardiola was gone.

The most successful four-year period in the history of the club was over, with Guardiola reluctant to work with the Barca board any longer.

Fourteen trophies were won under Guardiola's leadership and despite winning the treble under Luis Enrique in 2015, Barca have never been the same.

There's a reason why Messi is eager to move to Man City...

Guardiola with Barcelona

2017: Neymar and the PSG saga

Zinedine Zidane's first La Liga triumph as Real Madrid manager kickstarted a crazy summer for Barcelona.

Neymar stated his desire to leave the club and the Brazilian eventually joined PSG in a world-record £198m deal.

Barca signed Ousmane Dembele the same summer and also added Philippe Coutinho in January of 2018, two signings that really haven't worked out as of yet.

You get the feeling the Blaugrana would not be in the mess they find themselves currently in had they kept hold of Neymar three years ago.

Neymar signs for PSG

2020: Goodbye Messi?

Zidane's second and latest La Liga win looks set to coincide with the departure of Barcelona's greatest ever player.

Messi himself was very vocal about the club's failure to keep up with their main rival in the league in 2019/20 after a shock 2-1 defeat at home to Osasuna.

"We were inconsistent during the season," Messi said. "Real Madrid did their thing. We lost a lot of points. We have to do some self-criticism. We are Barca.”

"Madrid did their job, but we helped them a lot in that.”

Messi vs Bayern

You dread to think what will happen at Barca if Real Madrid scoop the 2020/21 La Liga title...