Crowley started his career in 1997, for Mick Byrne's ShamrockRovers. Crowley found his chances extremely limited was confined to the fringes of the team.
Crowley joined First Division side, Dublin City in 2000, in the hope of finding more football. He ended up staying with the Vikings for five years and establishing himself as a quality player. In 2003, he won his first ever silverware, as Dublin won the First Division. After a brief spell at Waterford United, Crowley returned to Dublin in 2006. In his first season back, Dublin City did not renew their licence and subsequently folded.
Dundalk
After the liquidation of Dublin City, Crowley spent a season at UCD, before moving to Dundalk in 2007, who were managed by his old mentor from Dublin City, John Gill. He was part of the Dundalk squad which won the 2008 League of Ireland First Division.
Drogheda United
Crowley signed for Alan Mathews' Drogheda United in 2009. He stayed at the Boyneside for two seasons and became a fixture in central midfield. He re-signed for the club for the 2010 season, which turned out to be a disaster, with the Drogs finishing rock-bottom of the league with only four wins. Due to financial worries, Crowley's contract was not renewed for the 2011 season, so he was forced to seek a new club elsewhere.
Crowley signed for St Patrick's Athletic F.C. on 21 January 2011. He played for the club during their European adventure, as they beat ÍBV from Iceland and Shakhter Karagandy from Kazakhstan, before losing to Karpaty Lviv of the Ukraine, 5-1 on aggregate in the Third Qualifying Round.
Return to Drogheda
Crowley re-signed for Drogheda United ahead of the 2012 season. He was immediately made captain by manager, Mick Cooke and handed the number 16 shirt. After picking up an injury in a friendly, Crowley had to wait until the third game of the league before making his second Drogheda debut, getting sent off in a 0-0 draw with Dundalk. Despite this early setback, Crowley ended up playing a huge role as Drogheda enjoyed a hugely successful season finishing 2nd in the league. He also started in centre-midfield in the EA Sports Cup Final as Drogheda beat Shamrock Rovers 3-1 in Tallaght - the first major trophy of Crowley's career. Despite a good season, Crowley was released by Drogheda on 27 November 2012 - a decision which shocked many of Drogheda's supporters.
