Memories of the horror eight-horse fall on Ipswich Cup day eight years ago came flooding back when four horses and riders came down in the Listed Gai Waterhouse Classic on Saturday.

Jockey Lacey Morrison was the most seriously hurt and was taken to hospital after her mount Stella Joy was the first to fall on the home turn.

Tony Pattillo, who rode Seconde, was also taken to hospital by ambulance following the pile-up.

Morrison was unconscious and treated on the track for several minutes after Stella Joy broke a hind leg and had to be destroyed.

Pattillo suffered a hip injury and was placed in a neck brace before being taken in a second ambulance to Ipswich hospital.

The club doctor reported Morrison regained partial consciousness before she was transported to the same hospital.

Jason Holder, who rode Centinelle, escaped serious injury and was able to walk back unaided to the enclosure along with Phil Wolfgram who was the last of the four runners to fall on Street Smart.

"I was in the backwash and couldn't avoid the runners that fell in front of me," Holder said.

"Tony (Pattillo) was in a lot of pain but he was conscious.

"Unfortunately, Lacey was unconscious and didn't look too good."

The four-horse pile-up revived memories of the Ipswich Cup day carnage in 2000 when five riders were admitted to hospital following an eight-horse crash in the Ipswich Cup which was won by I Reign Supreme.

Two horses also fell in the Listed Eye Liner Stakes that day which ended the career of Gold Coast jockey Gary Doughty who lost sight in one eye.

Saturday's Waterhouse Classic was won on protest by the Bryan Guy-trained Bareena ($3.80 fav) who was second past the post, a short head behind Kiwi filly Bella Valentina ($13) with Dance Girl Dance ($5) a further neck away third.

Bareena's rider Ric McMahon alleged interference over the concluding stages and stewards upheld his objection.

Guy is now considering backing up Bareena in next week's Group One Winter Stakes (1400m) at Eagle Farm.