Buchanan achieved a personal best of 30.03 as he raced to sixth place on a course that took in the Olympic Park precinct.

Threlfall was 11th overall in a time of 30.19.

The championship was won by Liam Adams in 29.22.

It was Buchanan's first start in the national 10km road race.

"To be sixth was a highlight, as was the time," Buchanan said.

Buchanan was determined to lower his best mark of 30.32 and was well on track to run sub 30-minutes.

They were among a leading pack of about 20 until the 4km mark in Sydney.

"A few of the leaders quickened the pace and we were then in a second pack of five."

Hours spent running on Bendigo's streets or at Lake Weeroona and the weight training at the Athlete Development Program hub at Bendigo South East Secondary College paid off for Buchanan over the last two kilometres.

He is athletics coach for the ADP program at the Flora Hill-based college.

"It was a great course to run on," Buchanan said of being among of field of more than 720 in the 10km duel.

Buchanan won this year's Bendigo Bank Dragon Mile on Easter Sunday.

Threlfall from Bendigo Harriers was the Dragon Mile champion two years ago.

Buchanan's racing calendar includes several cross-country races on the Athletics Victoria circuit ahead of the Gold Coast 10km in July.