For many, Messi lifting the 2022 World Cup with Argentina was the moment where all debates were settled and he officially became the greatest of all time.
Put that question to England international Trippier, a World Cup semi-finalist and European Championship runner up, and he's likely to agree, based on his experience of playing against the Paris Saint-Germain star.
"The best player that I played against is Messi, of course," he explained on the latest episode of Simply The Best: "He's a magician on the pitch, you just can't get the ball off him."
Football is a game full of talent, though, and while the Newcastle and England full-back has nothing but positive things to say about the seven-time Ballon d'Or winner, answering the question of who is the GOAT will never be easy.
@goalglobal playing against 'magician' messi is a privilege 🤩 #messi #lionelmessi #laliga #football #futbol #soccer #fyp
♬ Timber Lane - Chris Alan Lee
Trippier was asked a number of tough questions, including one or two issues closer to his current home.
"The best joker [I've met] is Callum Wilson," he answered about his Newcastle team-mate, adding: "You know, obviously when you walk in, in training in the mornings, you just want to be nice and quiet. But he's coming in full of Red Bull every single morning.
"He's always laughing and joking, playing pranks. Certainly with me. He's always joking around with me, you know, with my clothes and stuff. So but yeah, he's one who keeps his spirit in the team."
Check out the full episode of Simply The Best with Kieran Trippier on GOAL's YouTube channel.