1. Mark Lennon played at club level for the Cronulla-Sutherland Sharks, the St George Dragons, the Castleford Tigers, the Manly-Warringah Sea Eagles, Hull Kingston Rovers, the Crusaders RL, as a fullback or scrum-half, however he could fit into any of the backline positions with ease making him somewhat of a utility back.
Mark Lennon originally began playing rugby league at an early age 10 for Gymea before moving to Miranda Magpies at age 11 and the joined the Como Jannali RLFC.
Mark Lennon missed the majority of the 2003 season because of injury, mainly due to a broken leg which meant he could only make a few appearances for the club that year and at the conclusion of the 2004 he moved to Manly-Warringah Sea Eagles.
Mark Lennon was originally signed as a depth replacement on an incentive-based offer for the beginning of the 2004 National Rugby League season and was seen as the long term option to take over from Luke Dorn who had been released from the club because of his arrival.
Mark Lennon returned to his original 'home' club side the Cronulla-Sutherland Sharks in 2007 for the first time since he originally signed for them as a teenager.
Mark Lennon made his debut for his new club during their home fixture against Salford.
Mark Lennon was released from Hull Kingston Rovers on 17 September 2007.
Mark Lennon signed with the Celtic crusaders in 2008 in the hope they would win a Super League licence and played in the National League Grand Final in 2008.
Mark Lennon made his debut for the Welsh national side during the 2001 season after qualifying to play for them through his parental heritage with his mother being born in Wales.
Mark Lennon scored a late try in the game v PNG but tore a hamstring and missed the Scotland and Lebanon game for the rugby league 2008 World Cup qualifiers.
Mark Lennon appeared in 2008 for wales v England then did not feature due to family circumstances in 2009.
Mark Lennon then made 5 more appearances in 2010 and 2011 in Wales' triumphant European Cup, and Four Nations campaigns.
Mark Lennon won caps for Wales while at the Castleford Tigers, the Manly Sea Eagles, the Hull Kingston Rovers, and the Celtic Crusaders 2001.
Mark Lennon was named in the Wales squad to face England at the Keepmoat Stadium prior to England's departure for the 2008 Rugby League World Cup.