Caulfield Cup winner Southern Speed defied a big weight and doubts over her ability to sprint well fresh with a dominant win in Thursday’s Listed John Dillon Stakes.

Shouldering topweight of 60kg, even trainer Leon Macdonald had his doubts about the four-year-old over 1400 metres first-up at Caulfield.

But she made it look easy, sustaining a strong run from near-last and jockey Craig Williams eased her down over the closing stages.

“The way she has come back, you’ve got to be happy,” Williams said after Southern Speed scored a soft three-quarter length win over Shout Out Loud and pacemaker Danzylum.

“It is great to see her win and win in that style.”

Macdonald was excited as he ran down from the viewing area to the mounting yard to greet his mare.

“She was the class horse of the race but she did have 60 (kilos) and the trip was probably against her. But that’s how good she is,” Macdonald said.

Southern Speed won her first three starts as a three-year-old but doubts surfaced about her ability to race well fresh last spring when she was easily beaten in her first two runs.

Macdonald said Southern Speed had come to hand well this campaign and he had expected her to be running home strongly in the John Dillon.

“She looked ready today,” Macdonald said.

“Her first couple of runs in the spring she was a bit long in the coat.”

Southern Speed held up the start of the Dillon when she cast a plate at the barrier but Williams said the mare took it in her stride.

“She had to overcome that but her attitude was great,” Williams said.

He said Southern Speed, who was among the last four runners into the straight, responded well to his urgings and he loved the way she powered to the line.

“When I was asking for a run she kept lengthening and lengthening,” Williams said.

“When I was going through the gears she had room to go and when she had to hit top gear, didn’t get inconvenienced once.

“It was a really strong gallop to the line.”

The $1 million Australian Cup (2000m) at Flemington on March 10 and The BMW (2400m) at Rosehill, both at weight-for-age, are her autumn goals.

But in the meantime she has a major showdown with unbeaten champion Black Caviar in the Orr Stakes (1400m) at Caulfield on February 11.

“That will be easy,” Macdonald joked.

“If we run a nice second I would be happy.”