The mantle for best sprinter in the country is up for grabs at Moonee Valley on Friday night and trainer Robert Heathcote believes he has the Moir Stakes defending champion and race favourite Buffering primed to the minute.

The six-year-old gelding has yet to win a Group One race despite earning more than $2.5 million in prizemoney.

He gets his chance yet again with the Moir upgraded this year from Group Two status.

"It's frustrating not having a Group One title but he has had some freakish runs that have knocked him off," said Heathcote.

"We bumped into Black Caviar and no-one beat her, we bumped into Sepoy and he was one in a 20-30 year racehorse, and Haylist knocked us off in the Newmarket.

"Maybe in a another generation Buffering would have won four or five Group Ones, conceivably."

This time round Heathcote has altered Buffering's spring campaign to give him the best chance of winning a Group One.

"I made a mistake last year with Buffering going to the Schillaci Stakes after his first-up run in the Moir and, whilst he won that, it took too much out of him," Heathcote said.

This time Buffering will contest the Manikato Stakes followed by the Patinack Farm Classic, both Group One races, where he finished sixth and eighth respectively last year.

"I'm confident going in that I have got the horse where I need to have him," Heathcote said.

"He's come back fitter and stronger from his spell and I've had one of those lead ups into tomorrow night's race where everything has gone right."

Among a crack Moir field are the Jason Warren-trained Bel Sprinter, Doomben 10,000 winner Epaulette and Blue Diamond winner Samaready.

Heathcote describes Buffering, the $4.40 favourite, as a "jump-and-run" horse and expects him to lead early from barrier six.