Happy 21st Winx.

The world's best horse on turf has done it again.

The champion mare made it 21 wins in a row with her dominant victory in the $500,000 Group One Turnbull Stakes, her debut race at Flemington.

Jockey Hugh Bowman was pretty relaxed after guiding the six-year-old through what co-owner Peter Tighe joked was an "armchair ride" for the "master of Winx".

"(It's) pretty special," Bowman quipped.

"No surprise, believe it or not."

But co-owner Debbie Kepitis couldn't hide her emotions, no matter how much a fait accompli the win at racing's "headquarters" seemed.

"That is brilliant," said Kepitis, again wearing her lucky black with blue and purple suit with purple streaks in her hair.

"There's just no words.

"Happy 21st.

"What a freak. An amazing horse."

As accustomed as he is to Winx's victories, trainer Chris Waller admits to feeling relief each time she wins.

"She makes us all look good in what she does," he said.

"There is no training manual for a horse like Winx.

"We've managed to get it right, but she makes us get it right."

Winx had only raced three times in Melbourne before Saturday, winning back-to-back Cox Plates in 2015 and 2016 at Moonee Valley as well as claiming last year's Caulfield Stakes at Caulfield.

The mighty mare's main goal is a record-equalling third Cox Plate on October 28.