Colchester United were denied a fourth successive win as a late Wycombe Wanderers goal earned them a share of the spoils.
It looked like a Kayode Odejayi goal and a resolute defensive display would again be enough to grab all three points, but a late Jon-Paul Pittman strike levelled things up five minutes from time.
At some points in the afternoon, the U's had been top of the table, but they ended the day in fourth as they maintained their unbeaten run under boss Aidy Boothroyd.
The U's named an unchanged side for the fourth game running as they looked to push themselves further up the League One table against their fierce rivals.
Backed by a strong travelling support, the U's had a brief sight of goal within a minutes as Platt laid off to O'Toole to drive a shot that went wide, but also just beyond the onrushing Wordsworth.
The visitors had started on the front foot, winning a series of throw-ins in and around the Wycombe area to test the home defence in the early stages.
The match was a little fragmented to begin with, as the home side suffered a number of injuries and free kicks were awarded their way. Batth went into the book after being adjudged to have pulled down Harrold as the striker spun away.
From the resultant free kick on twelve minutes, Duberry had peeled away to be in space in the area but, from eight yards out, he headed well wide of the awaiting U's goal.
The U's own views of goal had been limited early on, but should have done on 17 minutes. Odejayi did well to spin his man and lay the ball off to Wordsworth. The midfielder could have shot but moved the ball onto O'Toole who, just inside the box, shot over the bar from a central position.
But the U's took the lead in incredible circumstances midway through the first half. Duberry pushed the ball back to Shearer who took his time to make a decision with what to do with it.
He tried to move it onto his other foot but, by that time, Odejayi had closed him down. The striker nicked it off his toes and, despite having time to move it closer to goal, he struck first time from 25 yards out to slide the ball into an empty net.
A crunching tackle from Izzet sent Lisbie away and his cross was turned behind from a corner. From the resultant set piece, it dropped in the six yard box and Shearer grabbed it just before the U's striker pounced.
At the other end, Phillips chose to check back despite having space to go into and he laid it to Woodman. The defender stepped up and struck a shot, but it was always going wide and Williams was happy to watch it go by.
But it was the U's who were having the chances. O'Toole picked up the ball some 35 yards out and, spotting Shearer off his line, he struck in a long distance shot that the keeper managed to just about claw over the bar.
Tierney joined Batth in the book for a foul on Betsy down the right hand side, but the U's were seeing off any free kicks that the home side were having around their penalty area.
It was from open play that the home side had their next chance, as Phillips lost the ball and then regained it off Lisbie, before drilling in a low shot that Williams held comfortably.
There was a break in play ten minutes before the break as the referee went off for treatment, and was eventually replaced - with the U's fans giving him very little sympathy!
When play eventually restarted, the U's again went close as they worked the ball around the Wanderers box. O'Toole's shot was mishit and when it came back in again, Odejayi lifted his header over the bar.
Harrold finished the half in the book after his ongoing tussles with the U's centre halves, and the U's went in a goal to the good after a half of working hard on and off the ball.
The home side replaced Pack with Bloomfield for the second half, as the ex-Ipswich trainee tried to turn the tide in the Wanderers' favour.
Harrold was the first to go close though, with the ball knocked back to him by Phillips. The striker hit the shot on the turn, but dragged it well wide of the target.
The U's responded well, pressing the home side who were trying to work a position on the ball with some patient possession. Tierney blocked the ball from a wicked Betsy cross when the ball did eventually make it into the area as the U's held firm.
Some patient possession of their own nearly set the U's up for their second. The ball was eventually helped into the right channel into the path of Odejayi and his low cross-cum-shot was collected at his near post by Shearer.
The home side made their second change ten minutes into the second half, and it was an attacking one. Pittman was the man introduced in place of Westlake as the home side went 4-4-2 for most of the second period.
It almost paid instant dividends as the impressive Davies again went close. The ball was played back into his path as he rushed onto it, but his shot swerved away from goal and beyond the far post.
The home side were keenly seeking a way back into the game, but the U's were remaining resolute at the back.
Chances had been hard to come by for both teams, but Wordsworth chested the ball down to Odejayi on 69 minutes and he moved the ball before hitting a low shot that Shearer saved with a sharp stop.
The U's made their first change a minute later, and the shot was to be Odejayi's last involvement in the game. Gillespie was the man introduced as the U's looked to exploit the space left behind the Wycombe defence as they sought the equaliser.
The match burst into life not long after the strikers introduction. From a corner, O'Toole and Woodman were on the ground and wrestling with each other. As Shearer got involved, the incident escalated and both the outfield players saw yellow.
Okuonghae was defending superbly as he held the U's back four in shape and he watched on as O'Toole took the ball across the edge of the area to try and clear from danger. Pittman got in the midfielder's way and went to ground in the area, but the referee adjudged the striker had dived and showed a yellow.
Betsy was replaced with twelve minutes to go, with Zebroski the man to come on as Gary Waddock added another front man to his armoury.
Wordsworth was booked a minute later - he looked like he had won the ball but the referee cautioned him for the foul thirty yards out.
It was one of a series of free kicks for the home side, but the U's remained solid and their fans got right behind them to see them through the final ten minutes.
White and Pittman came together with eight left to go, and the full back saw yellow despite the clamour of the home fans for something more serious.
The U's made another change amongst those free kicks with seven minutes to go, Lisbie coming off to be replaced by Ifil for the dying moments of the match.
The visitors were left breathing a sigh of relief as the ball fell to Pittman from a cross on the left but, on the angle just six yards out, he dragged his shot wide of goal - so far wide that it went for a throw.
However, the striker did far better a minute later as a long ball out from midfield sent him away and he kept his composure to slot the ball home past Williams to level things up.
The U's nearly went ahead on 90 minutes as Shearer clawed it clear from under his bar under pressure from Okuonghae, before Wordsworth's effort was deflected over the crossbar.
The visitors then had a late shout for a penalty as O'Toole bundled his way through and went to ground, but the referee waved away the appeals.