Theo-Sackey-Mensah played for Under-14s in tournament in Woudenberg.
near Utrecht in June 2014. He was then listed by Soccerway website as being on the fringes of the Under-18 squad in 2016-17
He joined Stevenage on 1st July 2018. He had a loan spell with Great Yarmouth in February 2019 before spending the latter part of the 2018/19 season on loan to Welwyn Garden City.
He then enrolled at Loughborough University playing for their team in the United Counties League.
In July 2022 he was part of a Dereham team that played Norwich in a pre-season friendly.