Champion eventer Sir Mark Todd is eyeing his eighth tilt at Olympic glory as Eminent's new trainer prepares the international for Sydney's autumn carnival.

The 63-year-old refused to rule out an appearance at Tokyo 2020, telling reporters at Canterbury racecourse on Wednesday he wasn't ready to transition to full-time training just yet.

"I do have that other side of my life at the moment. How long I keep going at that I don't know," he said.

New Zealand's favoured son helped the nation qualify an eventing team for Tokyo with the Kiwis scraping through in seventh at the 2018 FEI World Equestrian Championships in September.

Sir Mark won back-to-back individual gold at the 1984 and 1988 Olympics, retired from the sport after winning bronze at Sydney 2000 before making a triumphant return eight years later in Beijing.

During his break he turned to training racehorses, achieving success with Bramble Rose in the Group One New Zealand Oaks and 2007 Wellington Cup with Willy Smith, considered a Melbourne Cup contender until injury stopped short his career.

Sir Mark will compete in May at the Badminton Horse Trials in Gloucester, England, aiming to claim his fifth victory and beat his own 2011 record as the event's oldest winner..