Celebrating his 17th birthday last month, the highly-rated teenager has now signed a deal that runs until June 2022.



Joining the club in 2019 from Manchester City, Bellis has made an impressive start to life on the south coast, representing both the Under-18 and Under-23 age groups.



The teenager has netted seven times since his summer switch, including an impressive brace in Saints' FA Youth Cup success over Bristol Rovers in December.

Talking about the moment he sealed professional terms, Bellis said: “It’s something I’ve been waiting for since I started playing football when I was five years old.



"To do it at a club like this means a lot and I just can’t wait to get started properly now.



“I’ve settled in well; I get on with all the lads and everyone at the club has made me feel really at home."



Academy Director Matt Hale said: “Sam is someone we brought to the club through our recruitment team at the end of his schoolboy contract at Man City.



"He has a strong presence in front of goal and an eye for finishing. Alongside the experience of our coaches in the professional phase it will be great to see how he develops over the next few seasons.



"He's an extremely mature individual and knows exactly what he needs to work on to improve.”

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