Altherm JCR Yamaha Racing Team rider Maximus Purvis won the battle, but it was fellow Yamaha rider Bailey Malkiewicz who won the war.
Mangakino's Purvis was a force to be reckoned with in the Australian motocross nationals this year, winning four of the seven rounds in the Motocross Development (under-19 years) class, but it was Australian youngster Malkiewicz who ended up clinching the title.
Purvis, 17, dominated the day at Sunday's seventh and final round at Coolum, in Queensland, scoring back-to-back wins in the MXD class, although he still had to settle for third overall in the series.
"When Maximus was good, he was very, very good, but that wasn't always the case," said Altherm JCR Yamaha Racing Team manager Josh Coppins.
"I think he understands now what his weaknesses are and we will start working on those. Maximus is very good on soft, sandy tracks, but when the track is less technical and hard-pack, he's up against so many more riders who can go fast, and any small mistake is punished.
"For instance, he was lapping riders on Sunday who were battling with him at the previous event, where the surface had allowed anyone to go fast."
Malkiewicz placed fourth overall for the day at Coolum, but it was enough for him to win the series overall.
Runner-up to Purvis on Sunday was Bulk Nutrients WBR Yamaha team rider Hugh McKay, who also claimed the overall runner-up spot for the series.
"We want to thank Mike Ward at Yamaha Australia for making things happen. He put in a huge effort. It was a share deal for us ... we ran Jay Wilson for them here in New Zealand (earlier in the season) and they ran Maximus for us over there," said Coppins.