The 33-year-old spent six months at Camp Nou in 2018-19 and saw first hand how good the Argentine can be
Kevin-Prince Boateng has said that he found Lionel Messi to be so good during his stint at Barcelona, that he thought about hanging up his boots entirely.
Boateng joined the Catalan outfit in a surprise loan move from Sassuolo in January 2019, and managed to win a La Liga title in his six-month stint despite earning little playing time.
The 33-year-old would subsequently move on to Fiorentina and then Besiktas before joining Serie B outfit Monza ahead of the current season.
Recalling his time at Camp Nou in the 2018-19 season, Boateng admits that he could scarcely believe he was wanted by a club like Barca when he got word of their interest.
"The six months at Barcelona were incredible," Boateng told DAZN . "At first, I didn't believe it. I thought it was Espanyol who wanted me, not the real Barcelona!
"Training with Messi left me speechless. I had always said that Cristiano Ronaldo was the best in the world, but Messi is something else. He's not normal.
"While training with him, I felt inadequate for the first time in my career. He was doing incredible things. I felt like saying, 'I'm done, I'm going to quit playing!'"
Boateng has become something of a journeyman in his career, playing for teams in England, Germany, Italy and Spain. Though his career has included stops at major clubs such as Tottenham, AC Milan, Borussia Dortmund and Barcelona, Boateng admitted that he could have potentially accomplished more.
During his stint at Spurs between 2007 and 2009 in particular, Boateng said he looked to off-field extravagances to cover up for his on-field issues.
"When I was young, at Tottenham, it's true: I bought three luxury cars in one day, but there was so much pain inside me," he said. "I was trying to buy happiness. I wasn't happy. I wasn't playing. I wasn't well and so I was looking for something else. Sure, I would change that part of my past.
"Often, I trusted only my talent and, with the talent I have, without being arrogant, I could have done a lot more. Although, I have had a beautiful career anyway."
In the latter part of his career, Boateng has also focused on off-field activism, speaking out frequently against racism. Despite a host of ugly incidents across Europe recently, Boateng said that he has yet to see nearly enough change.
"In football, nothing has changed since 2013," Boateng said. "Maybe a few more fines, but nothing has changed. It's sad. It still happens. And it happens too much.
"Change comes from FIFA and UEFA. Us footballers, we're important, we try to speak, we use social media, we use interviews, but if it doesn't start from above, it's difficult for us.
"In 2013, I was saying, I hope that the kids in a few years don't know what racism is, and instead they're now hearing us talk more about it today than yesterday."