Lionel Messi certain Alex Ferguson will be left red-faced after Ronaldo remark

Lionel Messi's high-profile summer transfer from Barcelona to Paris Saint-Germain a year ago has not exactly gone to plan for the Argentine superstar.

Having found the net just six times in 27 domestic appearances in France, the 34-year-old was also unable to prevent PSG's Champions League round-of-16 exit against Real Madrid - seeing his first-leg penalty saved by Thibaut Courtois. The Ligue 1 match which followed the humiliation, when PSG clashed with Bordeaux, saw Messi and teammate Neymar booed by PSG fans.

Cristiano Ronaldo - Messi's long-term rival at the summit of football greatness - also was on the move last summer as he returned to Manchester United after 12 years away. The Portuguese star bagged 24 goals across 38 appearances, but was unable to halt the team's slide to a disastrous campaign.

Yet PSG chief Al-Khelaifi has struck a bullish tone on Messi's form and is confident his output will improve next season, as he explained: "There is no doubt that Lionel Messi has won the Ballon d'Or a record seven times, and it was not his best season.

"But after more than 20 years in Barcelona, he discovered a new country, a new city, a new league, a new team. A new culture. As well as his family, and he was injured also by the coronavirus. It was not easy for Messi last season, but next season we will see the best version of Messi ever."

That is a viewpoint that directly contradicts a former critique of Messi by Sir Alex Ferguson, who explained why he believed Ronaldo had the edge over Messi at the very top level - due to his adaptability to differing situations.

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The legendary former Manchester United boss signed a prospect from Sporting Lisbon in 2003 and helped Ronaldo develop into the iconic figure he is today. Ronaldo won three Premier League titles and the Champions League during his first spell in Manchester, prior to his move to Real Madrid in 2009.

Speaking back in 2015, Ferguson said: "People say 'who is the best player in the world?' And plenty of people quite rightly say Messi - you can't dispute that opinion.

"But Ronaldo could play for Millwall, Queens Park Rangers, Doncaster Rovers… anyone, and score a hat-trick in a game. I'm not sure Messi could do it. "Ronaldo's got two feet, he's quick, great in the air, he's brave - Messi's brave, of course. I think Messi's a Barcelona player."

Ronaldo has won five Ballon d'Or awards in a stunning career, while Messi pulled clear of the Portuguese icon by securing his seventh golden ball during the 2021 ceremony in Paris in November.

Messi picked up 10 La Liga titles at Barcelona as well as four Champions League crowns, while he finally tasted success at the international level last year as Argentina won the Copa America - their first title in 28 years. That ensured the two all-time greats were equal on the international stage after Ronaldo led Portugal to the European Championships title in 2016.