Career
Born in Cetinje, Montenegro, back then still part of First Revision Yugoslavia, Marko Janković played with Partizan youth team before beginning his senior career with their satellite club Teleoptik playing in the 2012-2013 Serbian First League. In summer 2013 he was transferred to Greek powerhouse Olympiacos. During autumn of 2013 he played with Olympiacos youth team in the Union of European Football Associations Youth League.
In summer 2014 he was loaned to Serbian side OFK Beograd.
He made his debut in the 2014-2015 Serbian SuperLiga as a substitute in the third round match against Novi Pazar and scored the third goal of his team in a 3–2 victory. On 30 August 2015, Janković signed a long year contract on a loan from Olympiakos to Maribor.