Colbon was a substitute in two pre-season friendlies in 2005 one against
Salford City Reds, and the other against
London Broncos. Liam made his first start of 2005 in the Wigan Warriors' 16–18 defeat by Wakefield Trinity Wildcats at
Belle Vue in which he set up a try for
David Vaealiki. His next appearance was an impressive performance against Hull when he scored his first try for Wigan. Liam came on as a substitute and scored a 90-metre interception try and later made a try saving tackle to help Wigan win the game 21–15. Liam was to make 5 more appearances for Wigan against;
Huddersfield Giants,
Leeds Rhinos,
Bradford Bulls,
Warrington Wolves and
St. Helens. By the end of 2005 he had made 9 appearances and scoring 2 tries. During 2006, Colbon only made one appearance during a pre-season friendly against
Leigh Centurions however this could be due to Wigan having a poor season and spending most of it fighting against relegation. Wigan sacked head coach
Ian Millward, and replaced him with
Brian Noble who used more experienced players in his squad such as
Nathan McAvoy rather than academy players. Liam continued to make appearances in the Senior Academy whilst continuing his education as he studied for a degree in Sports Studies at
Edge Hill University. In 2007, Colbon finished his university qualification gaining his degree and took part in a
Parachute Regiment training scheme which he completed and was awarded his beret. He started the season in the Wigan Warriors Youth Development academy but he impressed head coach Brian Noble and the after departure of
Chris Ashton he was given a first team opportunity in July against
Bradford Bulls. Afterwards he featured regularly in the Wigan first team scoring 6 tries in 13 starts and was rewarded with a new one-year contract for 2008. Speaking at the time he said "I'm glad it's all been sorted. I always wanted to stay here, it's a great club and there is a great spirit in the team". He was given the number 14 shirt for the 2008 season. Despite being picked ahead of teammate Mark Calderwood for most of the season and making twenty three starts he was not offered a new contract by Wigan and was allowed to leave.
Hull Kingston Rovers announced that they had signed Colbon and he was given the squad number five for the 2009 season. ==Hull Kingston Rovers career==