High-flying Berko saw their wings clipped by neighbours Tring Athletic in the FA Vase third round on Saturday.
The underdogs Athletic, 19 places lower than league leaders Berko, overcame their close neighbours and rivals in an entertaining cup tie at The Grass Roots Stadium.
It was played in front of 285 fans, the biggest FA Vase crowd in the southern half of the draw.
It was a terrific performance from Athletic’s players, who showed great spirit particularly in the second-half, to overturn the form book.
They defended superbly when required and restricted a potent Berko team, who have scored in every game this season.
The Comrades have played 27 games this season and Tring became the first side to stop them scoring and inflicted their first non-penalty shoot-out defeat since Slough Town knocked them out of the FA Cup in September.
Berko keeper Carl Tasker made the first save of note of the afternoon to keep out Max Hercules in the second minute.
Berko then lost possession and Tring kept the ball skillfully in the right hand corner before it was recycled back to ex-Comrades player George Carbery who whipped in a sumptuous cross to the near post where Chris Vardy had stolen in front of the big defenders to head the ball emphatically past keeper Tasker.
After a tough start to the season Vardy is looking like his old self and has now scored in his last two games.
It proved to be enough to put Tring in the last-32 of the competition.
Berko’s Adam Mead was as ever dangerous from free-kicks but Athletic’s netminder Jack Hopwood saved a long-range effort.
The visitors’ Chris Blunden shot over the bar against his old club to finish a rare Berko passing move.
Tring worked hard to continually surround Berko’s midfielders, so the Comrades frequently bypassed midfield with Mead and skipper Jon Munday hitting long balls out of defence.
As half-time approached Berko’s Steve Hawes fired over from a curling free-kick by Mead.
The visitors were hoping it would be a game of two halves, like the last meeting between the sides and they would come into the game playing down hill after the interval.
However, the hosts’ Vardy put the first real chance wide after the re-start.
Berko finally forced Hopwood into a real save from Josh Chamberlain while Hopwood again saved a Mead free-kick.
Then at 4.10pm the electricity supply to the ground cut out.
However the floodlights were back on to allow a resumption close to 5pm and the game resumed with Berko taking a corner. They forced several on the trot but the Tring defence held firm.
Alex Campana found Munday but his header into the ground bounced over the bar.
Another Berko effort was blocked on the line as they strove for the equaliser.
Ben Bateman was brought down, giving Mead the chance to take another dangerous free-kick but Hopwood was again equal to it.
Berko threw on three substitutes in a five-minute spell in a bid to pep them up for the last quarter of the game.
At the other end, Tasker saved from Luke Jones at the expense of a corner.
There was nearly a last-minute leveller as a long free-kick struck the post, but Kyle Anthony’s follow-up shot went over the bar from close range.
There were appeals for a hand ball but the referee waved them away.
This was the second season running Athletic have reached the fourth round of this prestigious national competition.
Despite a big improvement in their form of late, Athletic remain near the foot of the league table and need some points but do have games in hand. A couple of wins will see them shoot up the table.
Tring are one of just three South Midland sides left in the last-32 of the draw, which took place on Monday.
They have been drawn against Essex Senior League outfit Hullbridge Sports at home, to be played on Saturday, January 6, 2018.
Athletic have a break this Saturday before visiting Hadley on Wednesday for a Premier Division Cup tie.
Berko go to London Colney on Saturday hoping to remain unbeaten in the league.
They are still to agree a new date for their home Herts Senior Cup clash with Royston Town that was postponed from Tuesday, because of an FA delay on an appeal ruling on player eligibility in Town’s match in the previous round.
Tring: Jack Hopwood, Colm Parrott, Chris Mason, Mark Riddick, Luke Dunstan, George Carbery (Luke Jones 76), Max Hercules, Sam Joliffe, Chris Vardy, Tommy Twelves, Elliott Goward (Jack Read 81). Subs not used: Dave O’Connor, Jack Seaton, Steve Nott-Macaire.
Berko: Carl Tasker, Adam Mead, Max Farrelly, Steve Hawes (Dan Jones 72), Jon Munday, Kyle Anthony, Alex Campana, Ben Bateman (Sean Coughlan 68), Chris Blunden (Ashton Campbell 72), Josh Chamberlain, Ashley Morrissey. Subs not used: Jack Stevens, Dan Weeks.