"I'm concentrating on just keeping her balanced but when she hit the afterburners at the 150m mark today I just can't explain the feeling.
"I couldn't do that on any other horse,."
Waller echoed those sentiments.
The trainer put earmuffs on Winx after she blew the start in the Warwick Stakes two weeks ago and scared her fans before catching stablemate Foxplay to win by a half neck.
The earmuffs worked a treat with Winx jumping well but obviously not as well as Red Excitement.
"I was worried. I didn't think she was going to get there," Waller said.
"They turned the race on.
"It's never what you like to see when you've got a horse like her chasing but fair play to them.
"The horse held on and ran second, it didn't fall out and run last.
"With 400 metres to run I thought I was more concerned today than I was first up. I thought she was going to get there quite easily first up with her momentum but it is hard to gauge when you have a horse free rolling like that."
Adding to Waller's pressure, his two children were on hand at Randwick for the first time to watch the champion at work.
"They don't really follow racing but they know who Winx is," Waller said.
Winx joins New Zealander Gloaming and American star Zenyatta on 19 consecutive wins, six short of the unbeaten sprinter Black Caviar.
