Messi was selected ahead of tennis great Novak Djokovic to become the latest iconic name to secure the prestigious award.
The World Cup champion signed for the Major League Soccer side in July with the club slumped in last place in the Eastern Conference standings.
Messi quickly helped turn around Miami's fortunes and led them to their first ever trophy, lifting the League Cup in August.
The 36-year-old netted ten goals in seven games en route to securing silverware for the South Florida outfit.
The former Barcelona and Paris Saint-Germain maestro also helped his side reach the US Open Cup final but was unable to overcome Houston Dynamo in a game Messi missed through injury.
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Messi registered 11 goals in 14 games in total as Miami pulled themselves off the bottom of the table.
And now his impact on soccer in the United States has been awarded by TIME, who announced the star as their 2023 Athlete of the Year.
Messi becomes the first ever individual soccer player to scoop the award after the US Women's National Team picked up the first prize in 2019.
Other previous winners include basketball icon LeBron James, gymnast Simone Biles and baseball's top slugger Aaron Judge.
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Messi is enjoying some well-deserved time off after a dream 12-months that saw him captain Argentina to World Cup glory.
He also picked up a record-extending eighth Ballon d'Or award in October following his exploits in Qatar.
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Messi's influence on MLS has impacted and improved the growth of soccer in the United States with over 100,000 more subscribers to Apple's MLS Season Pass, registered on the day of his debut.
FC Dallas president Dan Hunt told TIME magazine that Messi's arrival in MLS has brought about new-found interest in the league whilst opening the door to further world-class talent entering the league.
He said: "We are having conversations with people that would not even be remotely possible five years ago," Hunt explained. "And I know we're not the only ones."