Danylyk was appointed on Friday after Matt Beeby stepped away from day to day involvement to spend more time with his family.
A popular figure at Harrison Park after making nearly 400 appearances and playing in the club's Conference side, Beeby still hopes to be involved helping the Blues on the commercial side.
Danylyk will continue as a player for Leek and current club captain, backing up Casswell on match days and in training. In a statement announcing the shake-up, Blues officials also confirmed that Jamie Cullerton would continue as an integral part of the management team and had taken on increased responsibilities.
Former number two Matt Beeby
Midfielder Danylyk is now in his fourth spell at Harrison Park after first arriving in 2002 from Stone Dominoes. In between, he has completed a season at Belper Town, a brief stint at Witton Albion and three and a half years with Altrincham.
The Blues also confirmed they'd re-signed central defender Darren Chadwick from EVO-STIK NPL First Division North Witton Albion on Friday.
Chadwick was at the club last season but left in the summer to join Scott Dundas at Wincham Park. He is the sixth former Witton player to sign for Leek in the last few weeks following the signings of Jon Beaumont, Lee Cropper, Niall Green, Kyle Diskin and Chris Baker.
Chadwick made 55 appearances for Blues last season scoring four goals after joining from Norton United.
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