The recently-appointed gaffer, who currently has something of a threadbare squad following a host of end-of-season exits, also warned his players that, with only a certain number of spaces up for grabs, they will have to impress him quickly if they want to avoid his ruthless streak.
Mansfield-born Clarke has several promising former scholars at his disposal including left-back Callum Cockerill-Mollett, midfielder Alfie Bates and striker Mitchel Candlin, and is expected to offer them a route to the first-team with football over the short pre-season period before looking at potential loans if they aren't ready for regular football.
Speaking via the Express & Star, Darrell said; "Everybody will be in my plans. We are having the youth team and the first team together for pre-season. It will be a mirrored pre-season.
"Everybody will be at the training ground for the pre-season period and I will be looking and analysing everything. I will be looking at all the players and seeing what’s what, and seeing how we go moving forward.
"Everyone will have a fair opportunity to impress, and they have to impress because I am pretty ruthless if needed."