The injury-plagued youngster has completed his first full pre-season since joining Fremantle at the end of 2007 and the shin, foot and groin problems that have followed him are gone.
He also received a massive vote of confidence from his teammates last December when he was voted into the club's leadership group after just 36 AFL games.
The 22-year-old said he was honoured to be recognised for his leadership ability, but it is the clean bill of health that has revived his self-belief ahead of the new season.
"Working really close with the fitness staff and the physios, we've finally found a program that works for me," Mayne told afl.com.au.
"Other years I haven't had a full pre-season and then sometimes I've been a bit worried - am I fit enough, are my skills under pressure, under fatigue good enough?
"But being able to train every main session, do all the weights, and do the majority of all the sessions, it finally gives you that self-belief that you are fit enough, and when it comes to game time you can hopefully put all of that together.
"I believe that my body can hold up."
Mayne arrived at Fremantle after battling osteitis pubis as a junior, and his 17 games in an accomplished debut 2008 season remain his best return in three years.
His 2009 campaign was virtually wiped out by stress fractures in his shins and he missed a 10-game stretch last year with an ankle injury that he tried to fight through for more than a month.
"Last year it wasn't due to me actually breaking down - I copped a pretty bad knock in the West Coast game in round six," he said.
"Where I was feeling the pain changed my running style and I was therefore always loading extra pressure onto a certain spot.
"[I was] still pushing through the pain, playing through the pain because you want to play, and in the end it just didn't hold up."
How Mayne has handled himself in rehab has no doubt contributed to his elevation into Fremantle's expanded eight-man leadership group this season.
Faced with consistent setbacks, he said his sole focus while sidelined was what he could do in the gym "to make sure that when I come back out on the training track I'm not that far behind".
Former rookie Matt de Boer, 20, and Garrick Ibbotson, 22, have joined Mayne in the leadership group, and he said the trio would offer guidance to the club's first- to fourth-year players.
"There's 33 of us in the development group this year, so really try and be a leader for them, but also at the same time be learning from the senior players," he said.
On-field, Mayne said he would again be focused on providing the aggressive tackling he has made his trademark, while his set shot has received attention on the track.
"I've had the jitters before in front of goal, so I've really focused this year after sessions getting an extra 10-15 shots on goal," he said.
"I always believe you can improve - every player can improve - and working really closely with Pav on my goalkicking has helped."
