The Cobblers twice threw away the lead as they suffered a 3-2 defeat to Rochdale at Sixfields on Saturday afternoon.
A Matthew Lund hat-trick secured the points for the visitors, but this was a hugely frustrating result as Town had twice led through goals from Matt Taylor and Sam Hoskins.
The team's defensive frailties once again came to the fore, with all three of Lund's goals avoidable, and the Cobblers have now lost five of their past six matches in Sky Bet League One.
Add into the mix the FA Cup humiliation at non-League Stourbridge on Tuesday night, and the pressure is beginning to grow on manager Rob Page.
Town have now dropped to 15th in the table, but are still six points above the relegation zone.
The Cobblers led after just 16 minutes through Taylor's free-kick, but allowed Dale to level three minutes later, and they repeated the trick in the second half.
This time Hoskins fired Town in front on 57 minutes, only for Lund to level again six minutes later, before netting the winner a further four minutes later.
The Cobblers made just one change from the team humbled in the FA Cup at Stourbridge, with John-Joe O'Toole back after suspension and replacing Marc Richards.
Town switched their formation from 4-4-2 to 4-1-4-1, with Jak McCourt sitting in front of the back four, and Paul Anderson and Hoskins out wide.
Taylor and O'Toole were the central midfielders, and it was clear from early on the midfield four had been told to get forward and support Revell to ensure he wasn't isolated.
After an even opening, it was Rochdale who carved out the first opportunity, but Oliver Rathbone flashed a volley over the top from 12 yards after being teed up by a chest down from former Cobblers player Ian Henderson.
Dale could have been reduced to 10 men minutes later.
The Cobblers broke on a swift counter-attck and right-back Joe Rafferty took a risk in sliding in and tacking Anderson from behind when he was last man. The Dale defender took the ball but got a lot of the man as well, but referee Eddie Ilderton felt it was a fair challenge. If he had given the free kick he would have had to have sent Rafferty off.
On 16 minutes the Cobblers went ahead, and it was another piece of free-kick magic from that man Taylor.
There looked no chance of a goal with the free-kick a good 25 yards out and on the left wing, but with goalkeeper Conrad Logan perhaps anticipating a cross, Taylor whipped a low shot round the left side of the wall and inside the Dale goalkeeper's near post.
The goal was just the lift the Cobblers needed, but their lead didn't last long as just three minutes later Dale levelled.
Joe Bunney made a good run down the left and, after nutmegging Hoskins near the byline, sent in a low cross that rebounded off a couple of Dale players before the ball fell kindly to Lund and he applied the finishing touch from five yards out. It was a scrappy goal, and easily avoidable.
Taylor almost restored the Cobblers lead with another free-kick from an almost identical position to the first, but this time the ball flew the wrong side of the post.
On 36 minutes a lovely piece of play saw Hoskins collect McCourt's raking pass on the right, beat his man and fire in a low cross that was just behind Revell, but the striker tried a back flick that drifted just wide, the ball agonisingly rolling too far in front of the onrushing Anderson and Taylor.
Once again, Dale responded with a great chance of their own, and this time Steven Davies headed wide from eight yards out with the goal gaping, Bunney once again providing the cross from the left.
Early in the second half, the Cobblers were denied a second goal by an excellent reflex save from Logan, sticking out his right hand to turn O'Toole's snapshot from six yards wide.
Page made an early change and brought on Marc Richards to replace McCourt as Town reverted to a 4-4-2 formation.
Dale wasted a great chance to take the lead on 55 minutes, with an unmarked Rathbone heading over a Joe Thompson right-wing cross when it looked easier to score, and the visitors were made to pay moments later as the Cobblers went 2-1 up on a counter-attack.
Richards played the ball out to the right to Hoskins who ran on to it and powered past Bunney, raced into the penalty are and thumped a low shot across Logan and into the bottom corner. It was an excellent finish.
But, as in the first half, the Cobblers threw away their hard-earned advantage and allowed Dale a cheap equaliser.
Town were on the attack when a stray Richards pass infield gifted Dale possession. They broke dangerously but Town had the chance to clear their lines only for Richards and Dave Buchanan to collide with each other, and allowing Thompson to shoot.
His effort was blocked, but the ball fell to Lund who hammered it home.
Things went from bad to worse for Town on minutes when Lund completed his hat-trick, heading home a looping cross from close range. The Cobblers players claimed the Dale man had fouled Cornell, and the goalkeeper was certainly under pressure, but the referee saw no foul.
The Cobblers responded well to the setback, with Logan saving a low shot from Hoskins after he was set up by Richards, while at the other end Cornell made an excellent fingertip save to deny Henderson, although referee Ilderton bizarrely gave a goal-kick.
With time running out, the Cobblers huffed and puffed in search of an equaliser, but couldn't carve out a clear opportunity as Dale sealed the points and strengthened their position in the play-offs.
Cobblers: Cornell, Phillips, Zakuani, Nyatanga, Buchanan, O'Toole, McCourt (49m, Richards), Taylor, Anderson (74m, Potter), Hoskins, Revell. Subs not used: Smith, Gorre, Beautyman, Iaciofano, McDonald.
Rochdale: Logan, Rafferty, McNulty, Lund, Camps, Rathbone, ,Thompson, Keane, Davies, Bunney, Henderson. Substitutes: Lillis, Canavan, McGahey, Andrew, Mendez-Laing, Noble-Lazarus, Cannon.
Referee: Eddie Ilderton
Attendance: 5,247 (261 Rochdale fans)