Serena Williams, Rafael Nadal Biggest US Open Sportsbook Liabilities Following Round 1

In a shocking development, people are wagering on Serena Williams and Rafael Nadal to win the US Open.

Jokes aside, it's no surprise to see the duo receive public backing after their strong round 1 performances, but just how much love are they getting?

A lot.

As per data provided by BetMGM, the two stars are drawing the most wagers in the futures market.

On the women's side, Williams accounts for both the highest ticket percentage and the biggest handle.

The 23-time Slam champion has amassed 26.2% of the tickets and 26.6% of the handle, with her price dipping down from a pre-round 1 number of +4000 to +2800 after a win against Danka Kovinic on Monday.

Williams did open at +1800 when the odds first came out, but she moved longer after a poor run of results in the lead-up to this month's tournament.

Williams will have to get by the world No. 2 Anett Kontaveit in the second round. In that match, Williams is a +190 underdog, drawing 81% of the wagers and 58% of the handle at BetMGM.

In the men's draw, it's Nadal who's generating action. He has gotten 22.2% of the tickets, falling from an opening price of +800 down to +350 after an opening win over wild card Rinky Hijikata. Nadal accounts for 21.3% of the total betting handle.

The man that has gotten the most money is favorite Daniil Medvedev, who is listed at +225, the same price he started at.

Nadal has a tricky second round matchup as well, though he's heavily favored (-2100). His opponent is Fabio Fognini, who famously came back from two sets down to beat Nadal at the 2015 US Open.

Full tournament odds can be found here.