Peterborough left it late before celebrating their 2000th Football League outing with a first home win of the season, all three goals coming inside the final quarter of an hour when ex-Fulham youngster Calum Willock turned the game.
No one was more delighted than Posh boss Barry Fry: "This is the early Christmas present we needed for the team and fans. We have been awful at home so far but no one can argue about this result and it was a great showing by Willock who has taken a pay cut to come here." Posh's dismal London Road run looked like continuing when Paul Kitson put Diamonds in front, the 33-year-old former West Ham and Derby marksman pouncing just four minutes into the second period firing past grounded goalkeeper James Cullon after the ball rebounded off the post.
It looked as if Posh, lacking the goal touch of Leon McKenzie, recently sold to Norwich City, would pay the price for squandering chances in a poor first half.
Only a low drive from skipper Curtis Woodhouse and a diving header by defender Sagi Burton that was well saved by on-loan goalkeeper Jamie Ashdown, caused Rushden serious concern.
Posh coach Andy Legg almost grabbed an immediate equaliser after Kitson's goal, crashing a shot against the woodwork with Steve Thomson firing wide from the rebound but Fry's side didn't finally haul themselves level until the 78th minute with Willock seeing the ball in to the net after a blistering break by Richard Logan.
Willock looked set to score again before being brought down by Barry Hunter to give away a penalty that Woodhouse swept past Ashdown with seven minutes left and Posh substitute David Farrell wrapped things up with a devastating solo run and angled shot that left Ashdown a helpless spectator three minutes later.
Disappointed Diamonds manager Brian Talbot commented: "The team that wanted it most won, its as simple as that. In the past in lower leagues we could expect to dominate teams but I have come to the conclusion that some of our players are not good enough at this level."