Non-League Chorley claimed an unlikely place in the FA Cup fourth round as they proved too strong for a youthful Derby side in an extraordinary tie.
Connor Hall and Mike Calveley were the men on target as the National League North side claimed a 2-0 victory in what was theoretically an upset on a freezing afternoon in Lancashire.
Yet with the Championship visitors decimated by a Covid-19 outbreak at their club, the four division gap between the sides was wiped out, handing the initiative to the part-timers.
Derby, with interim manager Wayne Rooney and their entire first-team squad isolating, were forced to field a team made up from their youth sides in order to fulfil the fixture.
With an average age of just 19 and not a single game of first-team experience amongst them, it was an uphill struggle.
That the game went ahead was remarkable in itself. Quite apart from the coronavirus issue, sub-zero temperatures in Chorley over the past week had forced the sixth-tier side to rent covers to try to prevent their surface from freezing. Their groundsman even camped at the ground in a tent to try to keep the pitch heated overnight.
His efforts proved worthwhile as the Magpies seized the opportunity to make history for their club and took the game to a team they ordinarily might not have been able to compete with.
There was an early flashpoint when Derby's Cameron Creswell went down in the Chorley area attempting to go round former Bradford goalkeeper Matt Urwin after being played through by Isaac Hutchinson. The Rams felt they should have had a penalty but referee Kevin Friend ruled in Chorley's favour.
That was a rare moment of alarm for the home team, who soon established themselves as the stronger side.
Their approach may have been direct but it repeatedly troubled the visitors and paid off as they grabbed the lead after 10 minutes.
The goal came from a corner taken by Willem Tomlinson, with his deep cross leading to a series of headers in the Derby box. The visitors struggled to clear and former Bolton striker Hall got the final touch from close range.
The non-League side continued to dominate with Ollie Shenton shooting over and Hall volleying wide from an Elliot Newby cross.
Newby had a chance himself after a good run but shot over from the edge of the area before Tomlinson hit the bar with an effort from distance on the half-volley that looped over keeper Matt Yates.
Hall had another chance early in the second half but headed narrowly wide and Newby curled a shot at Yates. Arlen Birch then delivered an inviting cross into the Derby box but Calveley planted a header wide.
Calveley was not to rue the miss for long. Derby barely got a foothold in the game and former Port Vale midfielder Calveley made victory certain six minutes from time when he volleyed in from close range.
