Young forward, Cook, and towering defender, Alimi Adetoro, both impressed while on trial at Middlewood Road, and have been rewarded for their efforts by landing permanent deals in blue and white.
U21s manager, Neil Thompson, clearly liked what he saw, and it was confirmed this week that both players had completed their moves to Sheffield.
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Here’s what the duo told the club’s official website after getting their deals done…
“It’s a really proud moment for me and my family… I have worked so hard and for a long time for this and I feel like I deserve it. Hard work continues now.
“It’s been a difficult journey, I have had a lot of no’s, a lot of rejections but I’m happy I never gave up because, being here, it is all completely worth it.
“I came here on trial and did really well, and the club believed in me. It’s been positive, I like all the boys, the coach – Thommo has told me exactly what he wants from me as a striker, hold up play, runs in behind, pressing and having the right attitude.
“The rejections in the past made me more determined to prove everyone wrong and that I am good enough. I want to put myself out there and show people what I can do.”
“I am delighted, it’s been a long time coming and good to get over the line… I am a tall and physical defender with pace and I want to show everyone those qualities and that I can do a bit of everything!
“I played a couple of games on trial last season, they went well and I am here now and looking forward.
“Myself and Neil talk all the time and I know exactly what he wants from me. The club have faith in me and, of course, that makes me happy.”
The pair will both be looking to make their official debuts for the club next week when the U21s take on Swansea City in their opening game.