born in troon, scotland, he is a former scotland u21 and scotland b international who played as a centre-back. he started his playing career with queen's park before moving to dumbarton. a transfer to english side sunderland followed in 2004 but he failed to establish himself in the first team during his three-year spell on wearside. after loan moves to hartlepool united and sheffield united he was loaned to wolverhampton wanderers, where he became a first team regular and signed a permanent deal in 2007. following wolves' promotion to the premier league he fell out of favour and moved on loan again, this time to preston north end, but although they signed him permanently in 2010, he was never a regular and quickly moved to leeds united, with whom he won promotion to the championship in 2010. after losing his place the following season collins returned to sheffield united, one of his former loan clubs, for whom he made over 100 appearances. he lost his first team place in the 2014–15 season and joined port vale on loan in march 2015. he moved to america in march 2016 to play for the tampa bay rowdies. by the end of his 18-year playing career he had scored 35 goals in 583 league and cup appearances.