US Open champion Sloane Stephens is more motivated than ever to win another grand slam, thanks to the $4.6 million she received for her success in New York.

In a clash between two first-time Major finalists, Stephens was too good for American countrywoman Madison Keys 6-3 6-0.

With her victory, the 24-year-old secured the $4.6 million winner's cheque, adding to the $5.6 million career prize money Stephens has already won.

Asked if she was hungry to win more grand slams, Stephens said: "Of course. Did you see that cheque that lady handed me? Like, yes.

"If that doesn't make you want to play tennis, I don't know what will. So, yes, definitely."

An Australian Open semi-finalist in 2013, Stephens underwent foot surgery in January, making her return at Wimbledon.

Her ranking slipped into the 900s in July and Stephens said her Major success came as a huge shock.

"When I had surgery, I was not thinking that I would be anywhere near a US Open title. Nor did I think I was going to be anywhere near the top 100," she said.

"I was worried about my protected ranking, and I was worried about using my protected ranking to get in here. I used both of them already for grand slams and tournaments and to be able to play. I was thinking about all the wrong things.

"Once I kind of let that go and just realised that whatever is meant to be is going to be, that I worked hard to get here and, that's that, then I think a lot of that stress was relieved and I was able to just play free and run and compete and just get out there and get after it every match.

"I mean, there is no words to describe how I got here, the process it took or anything like that, because if you told someone this story, they'd be, like, 'That's insane.' I'm just happy to be here."