Reddy retired from professional football in 2007 after failing to regain his fitness following three operations from a hip injury he endured while playing with Grimsby Town in 2006.
He made his League of Ireland debut for his local senior side at Buckley Park on 15 March 1998, against Dundalk, at the age of 17, scoring two goals and giving Kilkenny City a 2–1 win.
Reddy was used as Town's striker, mainly playing alongside Martin Gritton, Matt Harrold or Colin Cramb throughout this season.
Reddy's season was interrupted by a hip injury in March, and as a result, he did not complete another ninety minutes for the remainder of the campaign.
Slade opted to play Reddy from the start in the final at the Millennium Stadium against Cheltenham Town, but he was substituted due to receiving a concussion after a clash of heads.
Grimsby attempted to use Junior Mendes and Gary Cohen to help cater for Jones in attack, and the club lost the game 1–0.
After failing to secure promotion, his manager, Russell Slade, resigned, and Reddy requested to be put on the transfer list.
Grimsby had also made the signing of striker Isaiah Rankin in the hope of combining the pair in an attempt to make a second assault on promotion from League Two, but Michael still had a persistent hip injury.
With Reddy interested in leaving Blundell Park, he subsequently ignored contract talks in favor of potential offers from Bristol City.