FRICKLEY were sunk by a late brace when they entertained Retford in their last pre-season friendly before the UniBond Premier League kicks off this weekend.
The defeat leaves manager Billy Heath with one or two problems to be ironed out before the start of their campaign.
United finished top of Division 1 last season and were only denied a Premier spot because their ground did not meet the necessary criteria.
And the visitors showed they were no pushovers in the early exchanges, denying the lacklustre Frickley attack anything in front of goal as neither side looked likely to make the breakthrough in the first 45 minutes.
Mick Godber had the first real chance when he shot wide when well placed in the third minute, while Adam Nicklin reacted quickly in the 28th minute to snatch the ball of Stewart Copnell's toes.
Chances were few and far between for Heath's men, although Chris Davies put a first-time volley inches wide.
Although no changes were made to the attack immediately after the interval, there was an improvement with Davies whipping in a cross in the 49th minute, which was headed back by Rob Pell before the ball was diverted off the line.
Copnell had a shot blocked by substitute Jon Hood in the 52nd minute and Godber put the rebound into the side netting, while Davies had a 30-yard drive well held by United 'keeper Chris Kingston two minutes later.
Dean Jones came close from a Davies free-kick before Copnell beat the offside trap a minute later, only to be foiled by a full-length save from Hood.
In the 65th minute Scott Brough rounded his man on the right and hammered in a cross which Stuart Ludlam managed to clear under pressure from Lee Morris.
Billy Heath began to ring the changes in an effort to pierce the visiting defence although Retford broke through Godber in the 69th minute and he picked out Copnell who found the net but was ruled offside.
A good run by Dean Wilburn in the 84th minute was halted by a foul and Davies's free-kick was deflected out for a corner.
A mistake by Steve Robinson let in Godber who fired Retford ahead in the 86th minute, while Jonathan Groome gave away a foul on the edge of the penalty area in the 90th minute and Ryan Ford gave Hood no chance with a blistering free-kick to complete the United tally.
Frickley begin their UniBond Premier Division programme this Saturday with a visit to Witton Albion, kick-off 3pm, and then entertain Whitby Town next Tuesday, kick-off 7.45pm.
Frickley: Adam Nicklin (Jon Hood 46min), Scott Brough (Jake White 78min), Chris Gowen (Adam Pollock 56min), Danny Walsh, Steve Heath (Steve Robinson 70min), Dean Jones (Jonathan Groome 63min), Chris Hilton (Shaun Pierpoint 78min), Chris Davies, Lee Morris (Adam Lee 72min), Rob Pell (Dean Wilburn 75min), Calum Selby (Neil Towler 53min).