Aside a spells with Pahang FA in 2004 and Sivasspor in 2007, the rest of his career was spent in his native Australia notably in the A-League with South Melbourne, Perth Glory, Parramatta Power and Sydney FC.

He also played for Carlton SC, Melbourne Heart, Dempo, Goulburn Valley Suns, Werribee City, Dandenong Thunder, Whittlesea Ranges, Bulleen Lions.

Interest had been shown from Bayern Munich and Panathinaikos to sign Colosimo, but a knee injury sustained in a horror tackle by Andy Cole while on Socceroos duty kept him out of the game for most of the 1999/00 season, but made his return on 14 March 2000 to score against South Melbourne, who would eventually acquire the midfielder after the demise of the Carlton club.

[2] With his contract at Glory at an end, Colosimo was linked with a move to Sydney FC in 2008, receiving a hostile reception from Perth supporters[3] who let him know he was no longer welcome and was dropped from the starting side for some final matches.

What started as a spirited game finished in horror for Simon, as Andy Cole lunged into a tackle with his leg raised and studs showing, felling the Australian midfielder in full-flight.

Simon attended St Monica’s College in Epping up until year 10 as he then moved to the AIS in Canberra for a scholarship[12] His younger brother Anthony Colosimo played in the youth of Melbourne Knights FC[13] and with Bulleen Lions.