Andrew left the Acadia University Hockey program at the end of the 2012–13 AUS Hockey season and signed a professional contract with the Stockton Thunder, an ECHL affiliate of the Edmonton Oilers.[2] He appeared in a total of 66 ECHL contests for the Thunder until the end of the 2013-14 season with 26 goals and 43 assists. During the 2013-14 season,[3] he also spent time in the AHL after signing a professional tryout agreement with the Bridgeport Sound Tigers in December 2013.[4] Clark saw the ice in 35 AHL games, producing seven goals as well as twelve assists.[5]
He moved abroad upon the conclusion of the 2013–14 campaign, joining Esbjerg Energy.[6] Clark would lead the Danish league in scoring (36 games: 25 goals, 50 assists plus 15 games with nine goals and 16 assists in post season play) and helped the Esbjerg squad reach the finals, where they lost.[7]
After making noise in the Danish league, he was picked up by the SC Rapperswil-Jona Lakers of Switzerland's second-tier National League B (NLB) prior to the 2015–16 campaign.[8] He saw the ice in 39 regular season contests for the Lakers, scoring 19 goals while assisting on 28 more. On the way to the NLB finals, Clark played in 17 playoff games, tallying four goals and ten assists. The Lakers eventually fell short to HC Ajoie in the NLB finals.