Whelan joined the Blues in January 2025.

He began his career with Manchester United and featured in their under-18s and under-23s before making a move to Watford.

He only had a short spell with the Hornets, making just two appearances in the 2019/20 campaign.

After that, Whelan made the switch to Oldham Athletic, where he went on to make 89 appearances between August 2020 and July 2022.

He then moved to Solihull Moors and made 24 appearances for the club. During this time he also went on loan to Gateshead in February 2023, before making the move permanent in the summer of the same year.

Callum played 63 times for The Heed, and scored 13 goals.