Cairnie, who attended
Ardrossan Academy, made his debut for
Greenock Morton in the
Scottish Championship on 29 March 2014, in a defeat against
Queen of the South. In May 2014 he signed a two-year full-time contract with the club, keeping him at
Cappielow until 2016. Cairnie had a spell on loan with
Ardrossan Winton Rovers, who he previously played with at youth level. With the club, Cairnie scored two goals, helping them to win the
Ayrshire District League. In October 2015, Cairnie moved on loan to
Scottish League Two side
East Stirlingshire until 6 January 2016. He made his Shire debut in a home victory over
Elgin City and scored his first senior goal in a 3–1 win over
Montrose at
Ochilview. Cairnie was released by Morton at the end of April 2016, and signed for Ayrshire Junior side
Kilwinning Rangers. He quickly moved on to Ardrossan Winton Rovers for the third time, when ex-Morton coach Sandy MacLean took over as manager. ==Honours==