The world's nine highest-earning sportswomen over the past year are all tennis players, according to research by US business magazine Forbes.

Japan's Naomi Osaka tops the list with earnings of $37.4m (£26.3m), ahead of Serena Williams with $36m (£27.2m).

World number one Ashleigh Barty is third with income of $13.1m (£9.9m).

United States international footballer Alex Morgan is the only athlete from outside tennis in the top 10, earning $4.6m (£3.5m).

Morgan, who gave birth to her first child in May, earned $4.2m (£3.2m) of her income through endorsements during the span of Forbes analysis - between 1 June 2019 and 1 June 2020.

The US women's team, winners of the Women's World Cup in July 2019, are currently in dispute with their federation, appealing against a judge's decision to reject their claims of being underpaid compared with the US men's team.

Osaka and Williams have both broken the previous record for annual earnings, set at $29.7m (£22.3m) in 2015 by Russian tennis player Maria Sharapova.

In a list of the world's 100 best-paid sportspeople published by Forbes in May, Osaka (29th) and Williams (33rd) were the only women.