Northampton scored a try three minutes from full-time to claim a 30-23 Aviva Premiership win over London Irish at the Madejski Stadium on Sunday.
Northampton took the lead in the tenth minute when Noah Cato slid over for a try in the corner. Stephen Myler was wide with his conversion attempt.
But the hosts bounced back and within 15 minutes the game had been turned on it's head. Adrian Jarvis' penalty goal reduced the deficit to two, before Delon Armitage scooped up Sailosi Tagicakibau's offload to crash over for a try.
Jarvis added the conversion and the Exiles were five in front.
Myler's penalty goal on the half-hour made it 10-8, before a Jarvis penalty and Tagicakibau try extended the hosts' lead to ten points.
But Northampton were back to within a converted score on the stroke of half-time when Myler kicked his second penalty of the afternoon.
The visitors made an excellent start to the second half, scoring two tries in the ten minutes following the restart to take the lead.
Roger Wilson's try on 43 was quickly followed by Paul Diggin's effort, and Myler converted the second score from the touchline to make it 18-23 to the Saints. But there was plenty more drama to follow.
Declan Danaher's try just before the hour levelled the scores, but Jarvis was wide with the conversion that would have given Irish the lead.
The score set up a grandstand finish and it fell to Ben Nutley to grab the winner. His try on 77 minutes proved the difference between the sides, with Ryan Lamb adding the conversion for good measure.
For London Irish:
Tries: Armitage, Danaher, Tagicakibau
Pens: Jarvis 2
Tries: Cato, Diggin, Nutley, Wilson
Cons: Lamb, Myler
Pens: Myler 2
London Irish: 15 Delon Armitage, 14 Topsy Ojo, 13 Jonathan Joseph, 12 Daniel Bowden, 11 Sailosi Tagicakibau, 10 Adrian Jarvis, 9 Ross Samson, 8 Chris Hala'ufia, 7 Richard Thorpe, 6 Declan Danaher; 5 Matt Garvey, 4 Nick Kennedy (c) 3 Faan Rautenbach, 2 David Paice, 1 Max Lahiff.
Replacements: 16 James Buckland, 17 Clarke Dermody, 18 Paulica Ion, 19 Kieran Roche, 20 Jebb Sinclair, 21 Tom Homer, 22 Jonathan Spratt, 23 Darren Allinson.
Northampton: 15 Paul Diggin, 14 Vasily Artemyev, 13 George Pisi, 12 James Downey, 11 Noah Cato, 10 Stephen Myler, 9 Martin Roberts, 8 Roger Wilson, 7 Calum Clark, 6 Samu Manoa, 5 Christian Day, 4 Mark Sorenson, 3 Paul Doran-Jones, 2 Andy Long, 1 Soane Tonga'uiha.
Replacements: 16 Ross McMillan, 17 Alex Waller, 18 Brian Mujati, 19 James Craig, 20 Ben Nutley, 21 Ryan Glynn, 22 Ryan Lamb, 23 Tom May.
Referee: Andrew Small