Spencer Keller played for Norwich's Under-18s during the 2017/18 season. A pupil at Langley School, he was part of the school’s U15s squad lifted the English Schools FA Playstation Small Schools Trophy in May 2017 for their age group, beating Ellesmere Port Catholic School, from Cheshire, at Derby County’s Pride Park stadium. Keller was man of the match after scoring a hat-trick 

On 30th June 2018, it was announced that he had signed a contract to be an Academy Scholar, playing for the Under-18s.

On 9th May 2019, it was announced that he would be leaving Norwich when his contract ends. After being out of the game through injury, he had a short spell with Leiston from December 2021, making 12 appearances.

He then joined Kings Lynn in June 2022 but was released at the end of the 2022/23 season.

He signed for Leiston on 29th June 2023 on a two year deal..