Murphy started his career at Cobh Ramblers, progressing through the club's youth system before breaking into the first–team during the 2003 season. He then joined Cork City in 2007, and spent two seasons at the club. In December 2008, he joined Stevenage and helped the side win promotion to the Football League for the first time in the club's history the following season. Murphy was also part of the side that helped Stevenage earn back-to-back promotions to League One during the 2010–11 campaign. Murphy was released by Stevenage when his contract expired in May 2012, and subsequently joined Port Vale on a free transfer two months later. He switched to Macclesfield Town in January 2013, but left the club and returned to Ireland a few weeks later. He signed with Woking in September 2013, before returning to Cork City two months later. He rejoined Cobh Ramblers in February 2015.
Born in Cork, Republic of Ireland, Murphy started his career at Irish football club, Cobh Ramblers, as part of the club's youth system. He broke into the first–team the following year, and played a total of 77 times for the club, scoring nine times. In February 2007, Murphy joined Cork City on a two-year contract. He impressed during the latter stages of the 2007 season, and appeared a total of 32 times in his time at Cork.
In December 2008, he joined Conference Premier side Stevenage on a short–term contract, and was assigned the number 7 shirt ahead of his first game. Murphy made his Stevenage debut in a 3–0 win against Lewes at Broadhall Way, providing the assist for Stevenage's third goal. Shortly after, he scored his first goal for the club in a 2–1 win against Kettering Town, scoring from close–range to restore parity in the match. He went on to make 20 appearances for the club during the 2008–09 season, but was sent–off twice in games against Kidderminster Harriers and Cambridge United respectively. However, the latter was rescinded. This subsequently meant that Murphy was able to play in the club's 2–0 FA Trophy victory against York City at Wembley Stadium, a competition in which he started six games. On playing at Wembley, Murphy said "I was delighted it was rescinded and I have the television footage to thank for that because it would not have been seen otherwise. It was hugely important for me to get the chance to play at Wembley". He signed a new contract with the club at the end of the 2008–09 campaign. The 2009–10 season witnessed Murphy continue to feature in the first–team, although this was constantly disrupted by injury towards the latter stages of the season. He assisted Stevenage's second goal in a 2–0 win against Kidderminster Harriers, and played a total of 25 games during the season as Stevenage won promotion to the Football League for the first time in the club's history.
Murphy played his first game of the 2010–11 season in August 2010, starting in Stevenage's 2–1 loss to Portsmouth in the Football League Cup, scoring Stevenage's goal with an effort from outside the area that was deflected in. In the same game, he was substituted at half-time after suffering a dislocated shoulder, and was subsequently ruled out of first-team action for a month. In September 2010, he featured for Stevenage's reserves in their 3–0 win against Colchester United reserves, but was substituted on the hour mark, and had to be "helped off the pitch". It was later confirmed that Murphy had broken his leg and would miss the majority of the 2010–11 campaign. After six months out, Murphy returned to first-team action on 12 March 2011, playing the first half in Stevenage's 1–0 away win at Wycombe Wanderers. In the club's following match away at Burton Albion, Murphy appeared as an 81st-minute substitute, winning a penalty that John Mousinho converted to secure a 2–0 victory. He played a total of nine games during the 2010–11 season, scoring once. This included three appearances in the 2010–11 League Two play-offs following Stevenage's sixth-placed finish. Following a 3–0 aggregate victory over Accrington Stanley, Stevenage earned promotion to League One after a 1–0 win against Torquay United at Old Trafford on 28 May 2011, with Murphy coming on as a 57th-minute substitute in the match.
After making no first-team appearances during the first half of Stevenage's 2011–12 campaign due to a "succession of little injuries", Murphy joined League Two side Aldershot Town on a one-month loan deal on 10 February 2012. He made his debut four days later in Aldershot's 1–0 home win against Hereford United, Aldershot's first home win since December 2011. During the game, Murphy suffered a slight calf strain, and was substituted after 69 minutes. He made just two further appearances during his loan spell, and returned to Stevenage in March 2012. Murphy was not involved in the latter stages of Stevenage's season, and made no appearances for the Hertfordshire side during the campaign. He was released by Stevenage when his contract expired in May 2012. Murphy made 54 appearances during his three years with the club.
In July 2012, Murphy signed for League Two side Port Vale on a free transfer, penning a one-year contract. He made his debut from the bench on 25 August, replacing Chris Shuker 74 minutes into a 3–1 win over Morecambe at the Globe Arena. However, he then became Vale Park's "forgotten man", as he struggled with hamstring problems whilst the team surged to second in the table in his absence. He finally made his full debut on 20 October, in a 4–1 home win over Wycombe Wanderers. On making his return to fitness he speculated that "if there was a hell for footballers that's what you'd do, sit in the stand watching games injured." He made only his third appearance of the campaign against Rochdale on 6 November, but having entered the game as a substitute he was forced off injured after only a few minutes due to a recurrence of his calf injury. He left the club by mutual consent in January 2013.
Murphy signed with Conference Premier club Macclesfield Town in January 2013, on a deal lasting until the end of the 2012–13 season. However, on 13 February, having made no appearances for Macclesfield, his contract with the "Silkmen" was cancelled by mutual consent as he wished to return to Ireland.
Murphy signed for Conference Premier club Woking after returning from Ireland in September 2013.
Murphy returned to Cork City in November 2013. He rejoined Cobh Ramblers in the League of Ireland First Division in February 2015.As of 23 May 2016.
StevenageFA Trophy: 2008–09
Conference Premier: 2009–10
Football League Two play-offs: 2010–11