Mirabelli began his career with Portugal FC of the Canadian Soccer League in 2010. He recorded his first goal for the organization on June 25, 2010, in a 3–2 victory over Milltown F.C.[1] He scored his first professional hat-trick in a match against Brantford Galaxy.[2] He assisted in Portugal's qualification for the postseason by finishing fifth on the overall standings. He contributed with a goal in the semi-final match against Brantford Galaxy, but Portugal was eliminated from the playoffs after losing that match to a score of 5–3.[3] Mirabelli returned to Toronto for the 2011 season and clinched his first regular season title with the club.[4] In the quarterfinals of the playoffs he scored two goals in a 4–3 victory over York Region Shooters, but their match went into penalties as their two-game series was tied by a score of 4–4 on goals on aggregate, and subsequently Toronto would lose in the penalty shootout.[5]
Mirabelli joined Toronto FC II on March 20, 2015.[8] He made his debut against the Charleston Battery on March 21.[9] Mirabelli was let go at the end of the 2015 season as his contract was not renewed .[10]
In 2016, Mirabelli signed with League1 Ontario side Vaughan Azzurri, making five league appearances and scoring two goals that season.[11] In 2018, he made added another five appearances and two goals in league play, and made another two appearances in the playoffs, scoring one goal.[12] In the winter of 2018–19, he played indoor soccer in the Mississauga-based Arena Premier League with the Caribbean Stars AC.[13]