Victorian stayer Red Alto has beaten the odds and an army of Chris Waller-trained horses to score a determined win at Randwick.

Brent Stanley was the only trainer to take up the challenge against Waller, who fielded nine of the 10 runners in Saturday's Cindy Sullivan Memorial Handicap (2400m).

When he saw the original nominations, Stanley put in a late entry for Red Alto who started at $9.50 despite his trainer's confidence he could win.

Ridden by Tye Angland, Red Alto raced just behind the pace and made his move in the straight where he went into battle with Vaucluse Bay ($6.50).

There was a head between them on the line with Stanley celebrating from Moonee Valley where debutant Mig Energy was successful.

"(Red Alto) was entitled to win that race," Stanley said.

"He's won a few in town now and that was his sixth win. He's run fourth in a Derby so he's got ability and it was good to see him win again.

"He gave him a great ride in the race and he was strong through the line. The other horse was going to get to him and he fought it off, which was great.

"I think it was a story because Chris Waller had so many in the race, but it's good that you can send horses up there and get the money."

Three of the Waller stablemates backed up from Warwick Farm on Wednesday and the favourite Raqeeq ($3.40), who finished fourth, won at Rosehill a week ago.

Waller said he kept as many horses in the race he thought could handle it.

"I'm happy to see Brent win it," he said.

"We probably only wanted to have three or four in the race, but when there were no other entries we kept them in.

"The slow pace didn't help some of our runners."

Stanley also had a winner at Wangaratta to cap his day.