[5][6][7] He represented the victorious Vic Metro team at the 2005 AFL Under 18 Championships, winning the Larke Medal as the best player of the tournament.

[8] As the son of John Murphy, a Hall-of-Famer and legend of the Fitzroy Football Club,[9] Marc was eligible to be taken by the Brisbane Lions under the father–son rule.

[10] However he exercised his option to decline the offer and nominate for the 2005 AFL National draft as he didn't want to leave Melbourne.

17 disposals, 11 kicks and 6 handballs – highlighted by his first career goal – earned him an NAB AFL Rising Star award nomination.

[13] However, he sustained a season-ending shoulder injury in round 13 against the Brisbane Lions, which effectively ended any chance he had of winning it.

However, an injury to prime midfielder Nick Stevens after round 3 saw Murphy attract the opposition's best taggers in most games.

Murphy continued his form in the 2009 season, establishing himself as one of the elite midfielders in the AFL, and averaging 25.6 disposals per game.

He was named in the All-Australian team for the first time in his career, on the half-forward flank,[28] and won his first John Nicholls Medal for best and fairest player at Carlton.

[30] Murphy started the year as strong as he finished 2011, becoming the favourite for the Brownlow Medal before a heavy collision with Patrick Dangerfield in round 8 where he sustained a shoulder injury.

At the end of 2015, it was speculated that Murphy might lose the Carlton captaincy when new coach Brendon Bolton declared that the club was going through a "real reset" which included reviewing the leadership.

Marc bounced back from an injury-filled year to produce one of his most impressive to date, averaging over 29 disposals for the second time in his career.

Even at the age of 30 and after a wooden spoon season, Murphy still expressed his commitment to the football club after signing a contract extension.

[1] Marc Murphy stepped down as captain after his injury plagued 2018 season, giving young leaders Sam Docherty and Patrick Cripps co-captaincy.

[41][42] Four months after his retirement in December 2021, Murphy reflected on his playing career at Carlton and stated that “It was definitely the wrong decision to sack Brett Ratten as senior coach and replace him with Mick Malthouse” and Carlton was in great form under Ratten and “stiff” to narrowly lose its semi-final to the West Coast Eagles in the 2011 season".

[50][51][52][53][54] Since 2010, Murphy has been an ambassador for the MAD Foundation, a Melbourne non-for-profit organisation helping disabled and disadvantaged young people.