A sliding doors moment kept Mauricio Pochettino and Lionel Messi apart in 2005. But 15 years later, their paths could well realign at Paris Saint-Germain.

Back when Messi was in the embryonic stages of a Barcelona career that has seen him win six Ballons d'Or, 34 trophies and score a world record 644 goals for a single club, a temporary switch to cross-town rivals Espanyol was mooted.

There he would have linked up with an uncompromising defender by the name of Pochettino, and the subsequent decade and a half could have turned out very differently.

"I remember that summer, he was so close to moving to Espanyol," Pochettino said ahead of Tottenham facing Messi's Barcelona at Wembley in a Champions League clash in October 2018.

"If he did, maybe he could have been the biggest star in Espanyol. We should be the Barcelona! He would have been my team-mate and maybe I would still be in Espanyol managing him."

It only would have been a loan move, but an 18-year-old Messi convinced Barca he was ready for a more prominent role in the team by producing a stunning display in a victory over Juventus in the Joan Gamper Trophy.

Fabio Capello was in the opposition dugout at Camp Nou and after 25 awestruck minutes, he approached his counterpart Frank Rijkaard to ask if he could take the Argentine wonderkid on a temporary deal.

Barca finally realized they had a generational talent on their hands and opted against letting him go.

"I'd started to hear about Messi when I was an Espanyol player – this small guy playing in the Barcelona academy, who had arrived from Argentina when he was 13," Pochettino said.

"And then I heard he was very close to signing for Espanyol. But because he was so fantastic in the Joan Gamper against Juventus and Fabio Capello praised him afterwards in the press conference, Barcelona changed their minds. They kept Messi at Barcelona."

2030 vision

Messi began his youth career with Newell's Old Boys in 1994 – the same year Pochettino left the club for his first stint with Espanyol – and has often been linked with a return to the Rosario side to end his playing career.

Pochettino has been out of work since being sacked by Tottenham in November 2019 and was reportedly approached by Barcelona to replace Ernesto Valverde two months later, but his request for more time to consider the offer due to his loyalties to Espanyol resulted in Quique Setien getting the job instead.

Still, Pochettino retained hope that he will still have an opportunity to join forces Messi.

"I want to return to Newell's with Messi," he told Radio del Plata last March. "I can still wait, [for an opportunity] and the best [possible scenario] would be in 10 years with Messi."

But with PSG's decision-makers showing minimal festive cheers by firing Thomas Tuchel on Tuesday, Pochettino has been gifted a potential opportunity to work with Messi far sooner.

Pochettino was on Saturday named as the successor to Tuchel. Sporting director Leonardo and president Nasser Al Khelaifi will no doubt hope his appointment helps tempt Messi to forego a reunion with Pep Guardiola at Manchester City and relocate to Paris when his Barcelona contract expires at the end of the season.

"He's one of the gods of football"

Pochettino may not have won a trophy with Tottenham, but he led them to four straight top-four finishes in the Premier League.

His crowning achievement was steering them to the 2019 Champions League final, which ended in a 2-0 defeat to Liverpool.

Spurs finished behind Barcelona in the group stage that season. Messi scored a double in a 4-2 win for the Blaugrana at Wembley, while a 1-1 draw at Camp Nou saw Pochettino's men edge Inter to the runners-up spot in Group B.

After Spurs lost the first leg of their semi-final to Ajax 1-0, Pochettino urged his team to play like Messi during the second leg in order to have another chance of taking on the Barcelona captain in the final.

"He's one of the gods of football. It's unbelievable, it's unbelievable. It's unbelievable, the desire and the capacity to fight with the ball at his feet, to fight without the ball at his feet," said Pochettino.

"What happens when he touches the ball? When he doesn't have the ball, it's unbelievable the character, how he presses, how he works for the team. If we play like him, for sure we are going to have a chance. Of course.

"But not like him doing what he does with the ball. If we play like him without the ball, with the desire that he showed, for sure we are going to have a chance to qualify for the final. If not no chance."

Should Pochettino's desire to work with "one of the gods of football" at long last become reality, together they will be expected to help PSG finally conquer their Mount Olympus: winning the Champions League.