Mack Griffith has runners from either end of the experience spectrum vying to provide back-to-back TAB Highway victories for the Mudgee horseman.

Late blooming five-year-old gelding Schedule is among the frontrunners for the Class 3 Highway Plate (1500m) at Rosehill on Saturday after his impressive effort to give Griffith victory in the series for country-trained horses at Randwick last month.

"He'll go close to winning," Griffith said.

The trainer is also unperturbed by the rain falling in Sydney.

Schedule, who has never been outside the top three in his six-race career, made light work of a heavy Randwick track.

Griffith said the extra distance would not be an issue either.

"Schedule is the up-and-comer," he said.

While Schedule has been lightly raced, Griffith's other contender on Saturday has racked up plenty of miles around country NSW.

Griffith acquired the Goree-owned Puzzling Wonder from the Anthony Cummings stable 17 starts into his career.

The move has paid dividends with the five-year-old record a second, third and a win for Griffith who pre-trains for Eduardo Cojuangco's Gooree operation.

"Being a Gooree horse you follow him most of his career so when he became available we thought we'd take a punt," Griffith said.

"They weren't very strong races but Rosehill is only a country class three race, so we thought we'll give him his chance.

"Anthony taught him him what horse racing is all about. We just have to keep him happy, and fit basically."