Barcelona and Argentina star Messi dethroned retired boxer Floyd Mayweather as the sports world's highest earner, raking in $127 million via salary and endorsement deals.
That put Messi ahead of long-time rival Cristiano Ronaldo, the Juventus and Portugal star who was second with earnings of $109 million.
Brazil and Paris Saint-Germain striker Neymar completed a sweep of the top three positions by footballers, coming in third with earnings of $105 million.
The fourth highest earner on the list was Mexico's middleweight boxing star Saul "Canelo" Alvarez with $94 million.
Alvarez, who defeated Gennady Golovkin last September to become the unified middleweight champion, inked the richest deal in boxing history last October, signing a five-year 11-fight contract with streaming network DAZN worth $365 million.
Evergreen tennis star Roger Federer was fifth on the list with total earnings of $93.4 million.
The bulk of Federer's earnings came through lucrative endorsement deals, with the 20-time Grand Slam singles champion pocketing $86 million.
Stars from the NFL and NBA rounded out the top 10 on the list, with Seattle Seahawks quarterback Russell Wilson sixth on $89.5 million, just ahead of Green Bay Packers signal-caller Aaron Rodgers ($89.3 million).
Los Angeles Lakers star LeBron James was the highest earning NBA player, with $89 million, while Golden State's Stephen Curry was ninth with $79.8 million.
Curry's Golden State team-mate Kevin Durant was 10th on the rankings with $65.4 million.
Former world number one Tiger Woods was 11th on the list with $69.3 million, which included an estimated $54 million in endorsements.
Meanwhile tennis superstar Serena Williams was the only woman to make the list, coming in at 63rd with earnings of $29.2 million.
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