Starting with his first appearance for City’s Under-18s, Nelson went on to play regularly for the Development Squad in 2020/21, featuring in a first-team squad during the Foxes’ UEFA Europa League campaign and then capped the year off with an Academy Player of the Season Award.
It was a remarkable feat considering Nelson had only ever played Under-16s football before the start of that campaign. He was a regular in Premier League 2, with 16 appearances across 2020/21, as well as featuring twice in the EFL Trophy as Leicester reached the third round of the competition.
Nelson also turned out for the Under-18s on occasion, playing four times in Premier League U18, scoring once, as well as making two FA Youth Cup appearances in Leicester's run to the fifth round.
In the summer of 2021, meanwhile, the then-England Under-18s star, who previously represented Scotland at youth international level, also featured often in pre-season, making his King Power Stadium bow in the 3-2 victory over Europa League winners Villarreal.
Nelson continued his progression during 2021/22, named in several Premier League and Europa League matchday squads while playing a prominent role for the Development Squad in Premier League 2, with 19 appearances to his name, alongside featuring in the Papa Johns Trophy and FA Youth Cup.
The first half of the 2022/23 season was spent out on loan at Sky Bet League 2 outfit Rochdale, where Nelson played 12 times in all competitions - 10 of those coming in the league - prior to returning to the Under-23s setup in January 2023.