Michael Marinaro was born on January 7, 1992 in Sarnia, Ontario, Canada.
Marinaro began skating as a two-year-old at Point Edward Skating Club in Sarnia before relocating to Strathroy at age 15. Early in his pairs career, he competed with Lindsi Disper.
In May 2007, Marinaro teamed up with Margaret Purdy. In the 2009–10 season, they debuted on the ISU Junior Grand Prix series and won the Canadian junior title. The pair placed eighth in The Hague at their first World Junior Championships.
In the 2011–12 season, Purdy/Marinaro won their first JGP medal — bronze in Latvia — and placed fifth at the 2012 World Junior Championships in Minsk. The following season, they won gold at their two JGP assignments, in the United States and Croatia, and qualified for the JGP Final, where they placed fourth. The pair took silver at the 2013 World Junior Championships in Milan, behind Haven Denney / Brandon Frazier.
In September 2013, Purdy/Marinaro and their coaches moved their training base from Strathroy to Komoka. The pair appeared at two senior Grand Prix events, the 2013 Skate America and 2013 Skate Canada International, finishing eighth at both. After placing fifth at the 2014 Canadians, they were assigned to the 2014 Four Continents and came in sixth. They announced the end of their partnership on May 27, 2014.
On June 3, 2014, Skate Canada announced that Marinaro and Kirsten Moore-Towers had formed a partnership, coached by Kris Wirtz and Kristy Wirtz at the Kitchener Waterloo Skating Club in southern Ontario. Moore-Towers said that they were adjusting their technique on lifts, stating: "Mike's former partner is much taller than I am, so the technique is a bit different; he has to work in a different way."
Having received two 2014–15 Grand Prix assignments, Moore-Towers/Marinaro placed sixth at the 2014 Skate Canada International and seventh at the 2014 Trophée Éric Bompard. They were fourth at the 2015 Canadian Championships and ninth at the 2015 Four Continents.
In March 2015, the pair relocated to Montreal, Quebec.
Moore-Towers/Marinaro began the 2015–16 season with a bronze medal at the 2015 U.S. International Classic – their first Challenger Series event. Competing in the Grand Prix series, they won bronze at the 2015 Skate Canada International and placed 7th at the 2015 Rostelecom Cup. During the short program at the Canadian Nationals, the two clipped blades as they began the twist lift, resulting in a hard fall. They finished fourth for the second year in a row. On March 11, Moore-Towers/Marinaro were added to Canada's team for the 2016 World Championships after Julianne Séguin / Charlie Bilodeau withdrew due to injury. They finished 8th at the event in Boston.
Moore-Towers sustained a concussion during training in Montreal on August 3, 2016; as the pair practiced a jump combination, she fell in Marinaro's path and he collided with her head. The pair withdrew from their Grand Prix assignments, the 2016 Rostelecom Cup and 2016 NHK Trophy. They returned to competition at the 2017 Canadian Championships.
GP: Grand Prix; CS: Challenger Series; JGP: Junior Grand Prix