O'Brien is one of many footballers who has faced adversity to reach the highest level.
Having moved from his birthplace, Brazil, to Australia when he was three, the Collingwood defender knows all too well the difficulties of adapting to a foreign culture.
But luckily for O'Brien there was always a football close by and a friend to kick to.
"Coming from a culturally diverse background where it's somewhat different and people need to understand your culture, AFL is one thing that can be shared passionately," he told afl.com.au.
"It's something that is very important to me. Australian football has given so many opportunities to me that I feel like I should repay [the league] in some way."
O'Brien's experience has led the 22-year-old to become one of many footballers pursuing a role in ensuring equality, hope and harmony for people of different backgrounds.
Speaking at the launch of an initiative designed to educate Australian children on the acceptance of differences in culture, ethnicity, language and faith – You Can Kick Goals – O'Brien said he acknowledged the importance of AFL football in his life and wanted to pass on his passion and story of success to children around Australia.
"I'd like to think I am an ambassador of sorts at the moment, because I think doing work and promoting the message of harmony is what being an ambassador is about," he said.
"I certainly have a passion for equality and hope and harmony for all people, so it's something I see myself doing for the duration of my career."
Department of Immigration and Citizenship state director John Williams said AFL football taught young people important community values such as respect, fair play, teamwork, harmony and leadership, and Australian football had become an ideal avenue for building closer links within the community.
"Australian football has a fantastic history of embracing players and communities from diverse backgrounds, with names such as (Ron) Barassi, (Alex) Jesaulenko, (Anthony) Koutoufides and (Peter) Daicos part of the game's heritage and today's players including Harry O'Brien and Bachar Houli and Nick Malceski," he said.
"The You Can Kick Goals resource not only promotes Australian football, but also highlights the importance of teamwork, leadership and values such as fairness, respect and harmony."
