Concerns have been raised about the state of women's sport in the wake of Forbes magazine's list of the highest earning female stars.
American tennis superstar Serena Williams again came in first on the list of the highest paid women in sports for the fourth straight year.
The business publication calculated that the 23-time Grand Slam singles champion earned $29.2 million in the 12-month period ending June 1 -- with just $4.2 million of that coming from prize money.
Japan's Naomi Osaka, who burst to international stardom with a stunning upset of Williams in the 2018 US Open final and went on to win the Australian Open in January, became just the fourth woman to earn more than $20 million in a year -- after Williams and tennis stars Maria Sharapova and Li Na.
Forbes pegged Osaka's earnings at $24.3 million, putting her second on a list dominated by tennis players.
However, Osaka's yearly earnings - while undoubtedly impressive - do not even gain her a place inside the top 100 combined male and female list.
Williams is the only female to make the male-dominated list of highest earning athletes in the world.
Even still, despite being the women's benchmark, the American still only comes in at 63 on the Forbes list published in June.
The Telegraph's Molly McElwee said the latest figures "showed a worrying downward trend in the earnings of elite sportswomen," with all but the first three in the women's top 10 experiencing a drop in income from the previous year.
"2019's highest overall earner, Barcelona's Lionel Messi, made almost $100m more than Williams," McElwee wrote.
"The top-ranked tennis player and Williams' contemporary, Roger Federer, raked in more than three times what she did, with $93.4m placing him fifth in the rankings.
"And though the top 15 women earned a cumulative $146m - $16m more than last year - when you omit Williams and Osaka's $20m-plus totals there was a decrease in earnings across the board. The average income of the eight other top 10 women dropped from $9.2m to just over $8m.
To put the extraordinary figures further into perspective, only 15 women made at least $5m in 2019 compared to around 1300 male sporting stars.
Former Wimbledon champion Angelique Kerber came in at third on the women's list with earnings of $11.8 million followed by this year's Wimbledon champion Simona Halep.
Forbes included prize money, salaries, bonuses, endorsements and appearance fees between June 1, 2018, and June 1, 2019 in the figures.
Every female star in the top 10 is a tennis player with US soccer star Alex Morgan (12th) the highest placed athlete from a different sport.
Morgan earned $5.8 million, most of it in endorsements.
Indian badminton star PV Sindhu and Thai golfer Ariya Jutanugarn were the other non-tennis players in the top 15.
*all figures are in $US