In the past fortnight alone, the Argentina international has become the first man to score five goals in a single Champions League game and broken his club's all-time goalscoring record, all at the tender age of 24.
Consequently, Beane, the man behind 'sabermetrics', is of the opinion that Messi is effectively priceless and therefore his value is impossible to quantify.
Indeed, when asked during an interview with The Guardian to name the most underrated player in the game, the American replied: "I'd actually say Lionel Messi. He's so remarkable, watching him play he's probably still undervalued.
"When you're scoring five goals in one Champions League match, there's no value that's too high."
Messi's treble against Granada on Tuesday night means that he has now netted 234 times for the Blaugrana, twice more than previous record goalscorer Cesar Rodriguez.
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