The former Olympian will head to Europe in September to captain the Black Fins team looking to claim an unprecedented third consecutive world title.
McMillan (31), who moved to Auckland to teach at St Peter's College in 2014 but remains affiliated with the St Clair Life Saving Club in Dunedin, said there was a quiet determination within the team to become the first nation to achieve a three-peat.
"We've definitely got that legacy and the history in the back of our minds that obviously motivates us.
"But I wouldn't say it's in the front of our minds.''
The 12-strong team attended a camp in Albany last weekend that included a 12-hour adventure race and discussion about its goals for the event.
"We didn't talk about the results, really. If we're looking at that, we're looking too far ahead.
"We're focused on being successful and what that looks like is different for everyone in the team.
"If we do our jobs right, then yes, there's a good chance we will get our hands on the cup.
"There's a lot of talk around about ‘owning' the cup. We don't own it; it's up for grabs every year.''
McMillan is a former professional athlete and attended the London Olympics in 2012.
These days, though, he balances teaching, parenthood and coaching with his training, which is a lot less intense than it used to be.
"In 2012, I was purely an athlete; that was my job.
"Back then I was doing 10 pool sessions and two gym sessions a week. Now I'm doing well under 10 in total - about four to five swims and two gym sessions.
"It seems to be keeping me pretty fit.''
McMillan teaches physical education and health and takes a year 7 class at St Peter's.
He had to be creative to fit in his swimming training and sometimes used the Parnell club to train while another coach took over his classes.
The Black Fins had only two new faces from the team that won in France two years ago but many were now at different stages in their lives, McMillan said.
"There's some young ones and quite a few at the other end.
"We've got to evolve and keep moving forward if we want to be successful.''
The world championships were made up of 40 separate events spread over two days.
The men's and women's teams would both compete in 10 beach events and 10 pool events and points will be accumulated throughout.
McMillan said he had planned to retire from surf life-saving competition after the 2014 event but he would not be prolonging the decision after this year's title crack.
"I'm getting very, very close to the end.
"This will definitely be my last world championships.''
