A former Ross County and Brora Rangers youth player, Tain native and Tain Royal Academy pupil Adam MacDonald began playing with Balintore and later Tain Thistle in the Ross-shire Welfare leagues before playing briefly with Invergordon in the North Caledonian League. Adam joined the Saints in October 2016 following a successful summer season with Tain Thistle in the Ross-shire Welfare League and quickly established himself as a first team regular at wing back.
A tenacious and hard working defender who is as much at home defending as he is going forward, Adam's performances on the park were recognised when he was jointly presented with the club's Young Player of the Year award at the end of the 2016-17 season.
A cruciate ligament injury at the start of the 2017-18 season saw Adam out of action for an extended period of time as he underwent a long rehabilitation. He made his return to the squad in November 2020.