The payout is much higher than in 1968, the start of tennis' professional era. The first US Open awarded a total of $100,000 in prize money. Only 6 percent of that, $6,000, went to the women's champion, Virginia Wade. The men's champion was slated to earn $14,000 but, because of his amateur status, Arthur Ashe brought home just a $20 per diem.
Since then, the prize money has skyrocketed. The champions earned six figures for the first time in 1983 ($120,000) and seven figures for the first time in 2003 ($1,000,000). In 1973, for the first time, men and women earned equal pay for claiming the tournament's title. That year, both champions received checks for $25,000.
At the 2018 US Open, $53 million will be awarded in total, making it the richest purse in tennis history.
It's not just Williams and Osaka who will be taking home a hefty paycheck. Here's the full breakdown of how much the other singles competitors earned at this year's Open:
Round of 16: $266,000
Round of 32: $156,000
Round of 64: $93,000
Round of 128: $54,000
Here's what 17-year-old Maria Sharapova bought after winning her first Wimbledon
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