Kris Commons was the only man wearing gloves on the frozen New Lawn pitch in the Nailsworth hills on a raw day Forest Green sent a chill wind through the Derby ranks.
Rovers, from the Blue Square Premier League, were threatening one of those glorious FA Cup upsets that makes this competition one of the most exciting and romantic sporting experiences.
Derby, struggling in the Championship and having just lost manager Paul Jewell through a sudden resignation, were not supposed to lose to non-League opposition for the first time in 53 years.
Certainly not under the stewardship of Chris Hutchings, the caretaker manager, who was in charge for the first of two games given to him to stake his claim at Pride Park.
Yet Rovers, playing in the third round for the first time in their 119-year history, had the temerity to go2-0 ahead inside the opening 20 minutes and then had the nerve to lead3-2 with just 18 minutes remaining.
The fact they did not pull off a shock was down to Paul Green's almost immediate equaliser and Commons, who not only made Derby's first two goals but won the match-winning penalty.
Darren Jones, the Rovers defender, tripped the former Nottingham Forest midfielder in the area and as the assailant departed for an early bath substitute Steve Davies hammered home his 87th-minute spot-kick to give County-and Hutchings a reprieve.
Whether this result is enough to earn Hutchings, who did not last long in jobs at Bradford and Wigan when he replaced Jewell, the post full-time remains to be seen.
Commons, however, believes he is the man for the job. He said: "It would be super for Hutch to take over. He is great coach – one of those you admire a lot and it would not disrupt the play we are trying to do."
Goalkeeper Roy Carroll, who was recalled to the Derby line-up after his two-week absence following his dressing room altercation with Jewell, was soon wishing he had stayed at home.
Jonathan Smith rifled home a 22-yard volley past his ears before Alex Lawless beat the former Rangers keeper inside his near post to get Rovers off to the best start possible.
Two Commons' free-kicks allowed Rob Hulse and Martin Albrechtsen to restore parity before half-time with free headers only for the home side to get their noses in front again.
This time defender Paul Stonehouse sent his shot bouncing over Carroll's dive and Forest Green, founded by a church minister in 1890, looked to have had their prayers answered.
Stonehouse said: "I thought we had done it and I'm gutted by the result but I don't blame Darren because he had to make the challenge and I would probably have done the same."
Goals: Smith (14) 1-0; Lawless (20) 2-0; Hulse (40) 2-1, Albrechtsen (45) 2-2; Stonehouse (72) 3-2; Green (76) 3-3, Davies (87pen).
Forest Green Rovers (4-4-2): Boston; Gill, Jones, Kempson, Stonehouse; Lawless, Fowler, Smith (Afful, 64), Clist; Rigoglioso, Mangan (Mohamed, 68). Substitutes not used: Robinson (gk), Platt, Preece, McDonald, Thomas.
Derby County (4-4-2): Carroll; Beardsley, Albrechtsen (Powell, h-t), Nyatanga, Camara; Teale 7 (Barazite, 71), Addison, Green, Commons; Varney (Davies, 81), Hulse. Substitutes not used: Bywater (gk), Savage, Villa, Barnes.
Referee: P Taylor (Hertforshire)
Booked: Forest Green Smith, Gill; Derby Commons, Hulse, Davies.
Sent off: Forest Green Jones (86).
Man of the match: Stonehouse.
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