This year's top earner from the sport of boxing, Saul "Canelo" Alvarez, earned just $2 million in endorsements, but his $92 million in salary/winnings matched those of Messi to place him fourth in the list.
Tennis star Serena Williams was the only woman to feature, coming in 63rd.
Among female athletes, the only one to emerge in the standings is the U.S. tennis player Serena Williams, with 25.7 million euros per year and a distant 63rd among the 100 published.
The magazine takes money, salaries and endorsements from athletes between June 2018 and June 2019 to break down its list, which has been published every year since 1990.
Mayweather, who topped the list in 2018 and four times in seven years, only had an exhibition match last December in Japan and did not crack the top 100, which is comprised of athletes from 10 different sports. He earned $7.4 million in salary/winnings, but picked up a colossal $86 million in endorsements, the most of any athlete on the list.
Ranked 83rd on last year's list, Kohli has climbed down to the 100th spot despite an increase of United States dollars 1m in endorsements.
Brazilian PSG star Neymar ($105 million) completed a hat-trick of footballers at the top of Forbes' list, listed at number three despite earning $10 million more in salary/winnings than the Portuguese star.
Los Angeles Lakers star LeBron James was the highest earning National Basketball Association player, with $89 million, while Golden State's Stephen Curry was ninth with $79.8 million.