Harlequins continued their disappointing start to the season by going down to their third Aviva Premiership defeat in five starts as they lost 18-13 to London Irish.
For the first 60 minutes, Quins were marginally the better side but a huge tackling effort from Irish prevented them from developing their customary free flowing game as the visitors too often gave the ball away. In addition there were three penalty misses from the Quins which cost them dear.
The game turned on its head as Irish scored two tries in quick succession through Blair Cowan and Alex Lewington and despite a solo effort from Danny Care, the Irish were able to hang on for a morale-boosting victory.
London Irish captain George Skivington returned after injury to make his first appearance of the season while John Yapp was given a first start at prop. Number eight Chris Hala'ufia was a late withdrawal with a knee injury to be replaced by Ian Gough with Kieran Low switching to the back row.
For Harlequins, Karl Dickson was at scrum-half with Simon Smith and Matt Hopper being introduced into the three-quarter line in place of Tom Williams and the injured George Lowe.
Irish suffered an early blow when they lost Low, with a shoulder injury after only two minutes but they received an immediate boost by taking the lead. Karl Dickson was penalised for illegal use of the boot at a ruck allowing Shane Geraghty to kick the resulting penalty.
Harlequins had the better of the opening quarter but it was 3-3 at the end of it with Nick Evans kicking a penalty after earlier missing a more straight forward one.
The first half hour was littered with errors as neither side could take advantage of the ideal playing conditions as the game was devoid of excitement. There was one 40 metre burst from Maurie Fa'asavalu which enlivened proceedings but that move fizzled out as Quins made another handling mistake.
The visitors received two quick setbacks. First they lost centre, Tom Casson, with an injury before moments later Geraghty put Irish back in front with his second penalty.
Evans responded with one for the Quins to tie up the scores at half-time but the Irish should have been ahead. Three minutes before the interval, the home side were awarded a penalty straight in front of the posts 20 metres out but Geraghty opted to take a quick tap which saw no reward.
With 30 minutes remaining, Quins brought on Care at scrum half in place of Dickson and he should have seen his side take the lead but Evans missed with an eminently kickable penalty.
Quins made a further change as Chris Robshaw departed to be replaced by Luke Wallace and they had another chance go ahead. This time replacement, Ben Botica, was given the kicking duties but his attempt from the half way line went narrowly wide.
The visitors were made to pay for those kicking lapses as Irish scored two tries in four minutes to dramatically change the course of the game. The home pack were becoming more influential which resulted in Cowan driving over from close range for his first try for the club with Geraghty adding the conversion.
Quins sought to respond but again they lost possession; Topsy Ojo capitalised with a delightfully judged kick which enabled Lewington to gather and skilfully evade Botica for the crucial try.
Quins fought back with a try of their own, Care skipped away from a ruck to run 25 metres to score for Evans to convert which set up a grandstand finish but the Irish just held on.