For all the world it looked as if Nathaniel Mendez-Liang’s exquisite second-half goal would be enough to earn Dale the spoils after a to-and-fro encounter, but there was to be a late, late sting in the tail.
In the final of three added minutes, Adam Smith’s long clearance somehow found its way through to Anderson who remained calm and produced a beautifully measured finish, lifting over the onrushing Conrad Logan, to rescue a point.
On the balance of play it’s hard to deny that Northampton didn’t deserve at least a draw from what was a well-contested game at Spotland, and it’s a point that further boosts their hopes of a mid-table finish.
Earlier, the first-half simmered and always seemed on the verge of bursting into life without ever doing so, the two goalkeepers not once brought into strenuous action.
But the second-half was a much livelier affair and truly hit lift-off when Mendez-Laing curled in Rochdale’s opener on 55 minutes, which prompted an impressive response from the visitors who several times threatened a leveller.
Time ticked away, however, and it seemed Rochdale had done enough to come away with all three points, but little did they count on Anderson’s dramatic late invention.
The Cobblers do drop a place despite the result due to MK Dons’ win over Gillingham, nonetheless this most certainly represents a point gained and another step in the right direction.
As expected, John-Joe O’Toole returned to the Cobblers team for the long trip north as he replaced Keshi Anderson at the tip of a midfield diamond, although Luke Williams missed out completely having failed to recover from a hamstring injury in time.
A brisk start to the game saw both sides show early promise without forcing either goalkeeper into action as Rochdale’s Joesph Rafferty went closest when curling narrowly over from 20 yards.
But despite the open, free-flowing nature of the first 10 minutes or so, a first-half desperately short on goalmouth action descended into a bitty affair thereafter with both defences on top.
Zander Diamond’s crucial header and Aaaron Phillips’ even more important acrobatic clearance twice prevented crosses from reaching unmarked Dale players, while Northampton were let down by a poor final ball at the other end.
A difficult opening did fall to Marc Richards, whose first-time shot sailed harmlessly over, before a livelier end to the half brought two chances for Rochdale, and in particular Nathaniel Mendez-Laing.
In the first instance he delayed his shot too long, allowing David Buchanan to recover, before he fizzed just wide from 20 yards, and that was that for the opening period.
The second-half opened up with a lengthy passage of Dale pressure as they bombarded the Cobblers penalty area with a series of dangerous crosses, all of which were repelled by the visitors who stood firm.
The hosts at least managed the first shot on target on 54 minutes but it caused few problems for Adam Smith who gathered Ian Henderson’s weak effort from range with ease.
As it happened, however, that was only the warning shot as just moments later and with the second shot on target, Rochdale broke the deadlock.
It was a fine goal too with Mendez-Laing curling a superb 20-yard shot into the top corner after Northampton had been caught short at the back having lost possession up field.
In response, Justin Edinburgh threw on Hiram Boateng and Shaun McWilliams, who made his professional debut, and after a scrappy period, the Cobblers were a lick of paint from levelling when, on 70 minutes, Paul Anderson’s low left-footed shot flicked the post and went wide.
That signalled the start of an intense spell of Cobblers pressure, during which they had two half chances and again hit the woodwork.
On as a substitute, Brendan Moloney waltzed his way into the box and had a shot blocked before Richards headed wide and then, for the second time in the space of five minutes, Anderson crashed against the post, this time via a header from Moloney’s looping cross.
The visitors lost their way somewhat thereafter as Rochdale hit back and threatened a second, but deep into stoppage time, Anderson finally corrected his radar.
Set through by Smith’s long clearance, the Northampton man raced through, kept composed and coolly lobbed Logan, sparking wild scenes of celebrations both from the players and the 345 travelling fans.
Rochdale: Logan, Rafferty, McNulty, McGahey, Andrew, Camps (Rathbone 75), Allen, Lund, Davies (Vincenti 59), Henderson (c), Mendez-Liang
Subs not used: McDermott, Wilson, Morley, Kitching, Gillam
Cobblers: Smith, Phillips (Moloney 69), Diamond, Nyatanga, Buchanan, McCourt (Boateng 61), P Anderson, Taylor, O’Toole (McWilliams 67), Smith, Richards (c)
Subs not used: Cornell, McDonald, Beautyman, K Anderson
Referee: Ross Joyce
Cobblers fans: 345