A defensive horror show condemned Leamington to an embarrassing home defeat as familiar frailties returned to haunt caretaker boss Wayne Powell on Saturday.
With Andy Gregory and Chris Murphy picking up injuries in midweek, defender Dale Peckham was drafted in from Clevedon Town on an emergency loan deal.
Stuart Herlihy and Nathan Davies returned to the starting line-up after sitting out the midweek
trip to Hednesford.
The visitors were the first to threaten, with Ian Sampson flicking a header just wide and then thrashing a shot wildly over from a good position before Simon Travis fired over the bar for Leamington after winning possession on the edge of the box.
Mark Bellingham was in the thick of the attack and fired a shot just wide before opening the scoring in the 18th minute.
Fine work on the right by Luke Corbett saw the ball pulled back from the touchline and Bellingham headed home from close range.
Corbett was unfortunate not to score himself moments later, striking the outside of the post after good work from Davies.
With Brakes in control, Travis saw a first-time effort cleared off the line and was then denied by the offside flag after putting the ball in the net.
Jordan Tabor struck the top of the bar with a free-kick for the visitors before they stunned Brakes with three goals before half-time.
First, Mark Draycott appeared to wrong-foot Chris Kiely to score in the 25th minute and two minutes later, strike partner Michael Bartley was on hand to stab home after Kiely could only parry a long-range effort.
Brakes' front two were still working hard to create chances and Corbett shot just wide after good pressure before Didcot extended their lead in the 39th minute.
Bartley, who had not scored prior to Saturday's game, took advantage of a static defence to shoot past Kiely.
The assistant referee had his flag raised, but to the fury of the home support, the referee overruled his offside call and the goal stood.
Leamington emerged from the dressing room fired up for the second half and Trott had to push a stinging drive from Marcus Jackson over his crossbar early on.
In the 52nd minute, Stuart Herlihy was impeded on the right, 25 yards out and Bellingham bent a powerful free-kick around the wall and into the bottom corner of the net to drag his side back into the game.
Brakes were denied several times by borderline offside decisions as they poured forward in search of the equaliser and just past the hour, they were back on level terms.
Travis played the ball into space on the left and Bellingham did the rest, sprinting into the area and slotting past the advancing keeper for his 13th league goal of the campaign.
Brakes held the initiative, but any hopes they had of building on it were shattered when Peckham was shown a straight red card for preventing Bartley from getting away from him as he bore down on goal.
The striker fell under Kiely's attempted challenge, but the initial misdemeanour had taken place outside the box, for which debutant Peckham paid the price.
The free-kick struck the defensive wall, but it was not long before the ten men fell behind, with Bartley taking advantage of defensive confusion to complete his hat-trick.
Brakes still looked capable of getting back into the game and Corbett fired a shot on the turn just wide. However, with time running out, Didcot sealed their victory with the goal of the game, Sampson curling a shot beyond the reach of Kiely.
The frustration became too much for Jackson, who became the second player to see red, appearing to raise his arm to Sampson as they tussled for possession on the left.