Clubs often delve into their academies when they need players outside of the transfer window or when certain prospects are showing a lot of potential.
Some clubs use their academy to plug a gap while certain players can be good enough to force their way into the starting XI and remain there.
Championship side Swansea City have one of the best academies in south Wales and they often produce some good young stars for the future.
Here are two emerging talents at The Liberty Stadium which could save the club millions in the future.
The young striker has been at the club since he was eight years old and he has been able to establish himself within the under-23 setup at the club.
Cullen has shown a lot of promise since a young age with an under-18 debut at the age of 13 and ten goals coming at under-23 level last season when he really began to establish himself in the development team.
The 20-year-old has made three appearances for the first team already and has his sights set on breaking into the senior squad across the next year or two if manager Steve Cooper decides to keep him on.
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Cullen would be good to fill the gap left by loanee Rhian Brewster when he returns to Liverpool upon the expiration of his loan deal and the quick striker with an eye for goal can be moulded into featuring as the lone striker.
He is certainly an emerging youngster to keep an eye on.
Kees De Boer
The Dutch central midfielder showed enough promise to be snapped up by the Swans in the summer of 2017 on a three-year deal from Ajax.
The 19-year-old has been a regular feature after breaking into the under-23 side while he has been knocking on the first-team door.
He made his debut for the senior squad at the start of the season when appearing as a substitute against Northampton Town in the Carabao Cup.
The teenager could be an excellent option in the middle of the park if Cooper played a part in developing the youngster and he would learn a lot off of the current captain Matt Grimes as well as Jay Fulton and George Byers.
De Boer still has a long way to go in terms of really being ready for regular Championship action but he could save the club money in the future.