PRINCE OF WALES'S STAKES 1 Maids Causeway (M Hills) 9-2 2 Karen's Caper (J Fortune) 11-2 3 Mona Lisa (JP Spencer) 25-1 Day four round-up

The 9-2 shot, trained by Barry Hills and ridden by son Michael, was always in the first two and took up the lead four furlongs out.

She was joined by Karen's Caper and the pair battled up the run-in before Maids Causeway got up by a short head.

Early leader Mona Lisa was third, just edging out Cape Columbine in fourth.

Maids Causeway had finished as runner-up to Virginia Waters in the 1,000 Guineas but the Newmarket was well down the field at York.

Maids Causeway is so brave and consistent, and would not be beaten From Seren Have your say on Five Live

Favourite Damson was also a disappointment and trailed in well behind the leaders.

There was a moment of anxiety as winning jockey Hills dismounted from Maids Causeway immediately after the line but it transpired that the filly was not injured.

"I thought she went lame coming to the line so I got off her as quick as I could, but thank God she has only pulled a shoe off," he said.

Bought by New York-born financial trader Martin Schwartz at the end of last season, Maids Causeway could now be aimed at the Breeders' Cup meeting at Belmont Park in his home city.

Winning trainer Hills said: "Full marks to her, she is seriously tough. I don't think she would mind going over a mile and a quarter and I would be excited about trying her over the trip.

"The Breeders' Cup is obviously going to be on her agenda, and I have entered her in the American Oaks too."