Furnell insists recruiting new players and retaining existing ones has been made more difficult by a switch from the Southern League to the Northern League.
The Cuckoos will compete against the likes of Spalding United, Stamford AFC and Wisbech Town in the Northern Premier League Midlands Division this season.
“The club actually has less travelling to do,” Furnell said. “But we have based our recruitment in the last couple of years on attracting players from the south so for them the travelling became a big problem.
“I lost about eight first-team regulars from last season in all positions and trying to get more northerly-based players to the club has proved difficult so far.
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“I’m not going to lie, but pre-season has been awful, a real struggle.
“But we will do what we can and try and consolidate as the season progresses. I am sure we will be okay in the long run.”
Among Yaxley’s losses are Jordan Macleod to Spalding and Joe Butterworth to Stamford.
Centre-back Spencer Tinkler has arrived at the club from Holbeach as Furnell hopes his’leadership qualities’ will help.
Yaxley host big-spending Spalding next Tuesday (August 17) after travelling to Walsall-based Sporting Khalsa for their opening game on Saturday (August 14).
Stamford and Spalding start at home against Loughborough Dynamo and Ilkeston respectively (3pm kick offs).
Wisbech Town host Coleshill in their opening fixture.