Born in Bar, he started playing in his hometown club FK Mornar. He made his debut for the senior squad in the 2004–05 Montenegrin First League. After 2006 when Montenegro separated and formed its own league, Kecojević still played the first six months of the 2006–07 season, when, during the winter break he moved to Serbia and signed with FK Teleoptik. Teleoptik is known for being FK Partizan's satellite club, and most better players end up having good prospects of later earning a chance in Partizan's main team, or other Serbian top league clubs.
Kecojević played with Teleoptik for two and a half seasons, before getting a chance in the Serbian SuperLiga by being loaned to Čukarički. There he became a regular player making 25 league appearances that season. Unsurprisingly, in the following summer of 2010, he signed a three-year contract with another SuperLiga club, OFK Beograd.[1]
Kecojević signed for Gaziantepspor in August 2012 on a four-year contract.[2] In a match against Beşiktaş, he attempted to go on the field in only briefs without any shorts on.[3]
On 9 January 2013, Kecojević signed for FC Zürich, after which club chairman Ancillo Canepa told journalists that "In Ivan we got an excellent, experienced player, focused one hundred percent on football."[4] He won the 2013–14 Swiss Cup and 2015–16 Swiss Cup with Zürich. In June 2017, his contract expired.
On 9 August 2017, Kecojević signed a one-year contract with Segunda División club Cádiz.[5] On 18 August 2019, he moved to fellow league team Albacete Balompié on a three-year deal.[6]
