Cameron Crockett has taken a measured approach with Mar Nero leading into the Highway Handicap at Randwick.

The seven-year-old came to the Mudgee trainer as a 19-start maiden with a habit of missing the start and has won three races under Crockett.

After the mare finished third at the start of her preparation last month on her home track, Crockett targeted Saturday's 1600-metre Highway (1600m).

"I set her two really hard tasks for a class three (horse) to prove herself where there were things against her," Crockett said.

Mar Nero carried 61kg in a Benchmark 50 Handicap (1400m) at Wellington and finished third.

She occupied the same placing 18 days later in an Open Handicap (1400m) behind the well-credentialled Galaxy Warrior at Dubbo.

"I gave her a break and did nothing, so that run's brought her right on," Crockett said.

"We haven't done anything specific to correct her barrier issues.

"She had 19 starts before I got her so she knew what she's supposed to be doing."

Crockett was also unfazed about Mar Nero's eight-day back-up from Dubbo saying her 2000m-win at Mudgee came nine days after her fifth in the Bathurst Cup.

"The quick back-up is ideal for her because she doesn't like to do much work at home," he said.

Leading Highway Handicap-winning trainer Matt Dunn has the favourite Cascata Rossa as he chases a 12th win in the races for country-trained horses.