Career
Muldoon started his career at home-town club Scunthorpe United as a winger, being released in his second year as a youth. After a mid-season at Doncaster Rovers he moved to lower league football, starting with Brigg Town. Muldoon subsequently represented Sheffield, Glapwell, Alfreton Town, Stocksbridge Park Steels, North Ferriby United and Worksop Town.
With the latter he scored 21 league goals during the campaign, attracting interest from Football League clubs.
On 15 May 2014, Muldoon joined on a one-year deal, and then quit his job as a plasterer in order to pursue being a professional football player. He made his début on 7 October 2014, coming on as a 58th-minute substitute during "s 1–0 Football League Trophy defeat against Walsall.
He made his Football League debut on 15 November 2014, coming on as a 68th minute substitution for Michael Rose in a 0–1 away loss against Portuguese Vale. He was released at the end of the season.
On 28 May 2015, he signed an initial one-year contract at after his release from Made his debut in a 1–1 home draw with Cheltenham and then managed to score his first goal for the Imps in a 1–1 draw with Eastleigh.
In January 2016 he signed a new one year contract extension.
