Boss Chopper has his eye on further youth development but stresses the importance of patienceMillwall manager Neil Harris hopes that the club's batch of promising youngsters can continue to make their mark on the first team throughout 2015/16.
Sid Nelson and Aiden O'Brien enjoyed breakthrough campaigns last time out, while Fred Onyedinma has returned to the club following a successful loan spell with Wycombe Wanderers.
Others, including Jack Powell, Alfie Pavey, Ben Thompson and Jamie Philpot, who scored on his first team debut in May, have been around the senior squad for some time.
And Harris, whose squad fly back from their training camp in Portugal at the end of the week, wants to oversee a production line of youngsters making the step-up from the club's Academy sides to the first team - but insists that process will take time.
"Last year Sid and Aiden played regularly and we all saw the attributes they had," the manager told millwallfc.co.uk.
"There is a long way to go for them as there is all the younger players. The boys have the attributes that we believe in but they are nowhere near the finished article. We have to keep nurturing them and improving them all the time.
"People like Kris Twardek, Kyron Farrell and Mahlon Romeo have travelled with us to Portugal and they have the attributes, which is why they are at the club and why we believe in them.
"We want these players to come through and develop and to form part of the group with the likes of Fred Onyedinma, Jamie Philpot, Alfie Pavey, Ben Thompson and players like that, but it does take time."
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