The central defender from Garvagh in Co. Londonderry, started out playing for Bertie Peacock Youths and was then in the Linfield Academy for three years as a teenager before moving to Rangers FC aged 16. After two years in Rangers’ Youth teams, Whiteside made the move to Partick Thistle’s development team where he spent the 2015/16 season before signing for Kenny Shiels’ Derry City upon his return home to Northern Ireland in the summer of 2016. The defender would make 8 appearances for the Candystripes, during which time he spent the first half of 2017/18 season on loan with Coleraine, for whom he made 19 appearances. After leaving Derry City in the summer of 2018, David Jeffrey brought the centre back to Ballymena United where he’d establish himself as a regular starter. Although he missed the 2020/21 and 2021/22 seasons through injury, Whiteside would go on to make 134 appearances for the Sky Blues, scoring twice. He represented the Sky Blues in Europa League Qualifying ties against NSI Runavik (Faroe Islands) and Malmo FF (Sweden). After six years at Ballymena Showgrounds, Whiteside signed for Linfield for an undisclosed fee on May 30, 2024, and made his debut on July 11, 2024, in a 2-0 defeat away to Icelandic side Stjarnan in Conference League Qualifying.

 

Whiteside is a former Northern Ireland Youth International at U16, U17 & U19 level, where he played under Linfield manager David Healy.