Harlequins secured their first win against Northampton since May 2013 with a hard-fought 20-9 victory at the Stoop.
It was a much-needed result for Quins, who began the day second from bottom in the Aviva Premiership standings, with Alofa Alofa's 11th-minute try and four penalties from replacement fly-half Tim Swiel proving the difference.
Quins were dealt an early blow before kick-off with England prop Joe Marler withdrawing due to a back spasm. Mark Lambert took Marler's place in the starting line-up with veteran Welsh tighthead Adam Jones moving onto the bench.
Following England's controversial midweek training camp in Brighton, where Sam Jones and Anthony Watson sustained serious injuries, head coach Eddie Jones and defence supremo Paul Gustard were at the Stoop to watch a number of their Test players.
Mike Brown's early charge yielded the first penalty of the afternoon for Nick Evans, but the usually reliable Kiwi sent the seemingly easy effort wide of the posts. Evans made no mistake after seven minutes, however, as the Saints strayed offside once more.
Quins' injury problems continued with Lambert and Jamie Roberts both leaving the field for treatment in a brutally physical opening quarter. Alofa, on his first start for the Londoners, finished off a sparkling counter-attack to put Quins 8-0 in front. It was just reward for a powerful start from the home team.
An exhausting period of phases eventually forced a rampant Quins defence offside with Stephen Myler finally getting his side on the board with a 19th-minute penalty.
The powerful outside backs of Quins were causing Northampton all kinds of problems with Roberts, Scotland winger Tim Visser and Marland Yarde all to the fore.
A powerful Saints scrum, spearheaded by tighthead Kieran Brookes, allowed Myler to trim Quins' lead to two points from the kicking tee. Myler had the opportunity to put the visitors ahead when Luke Wallace was penalised for hands in the ruck following a powerful charge from Luther Burrell, but the Saints number 10's penalty struck the post allowing Yarde to clear the danger.
The goal-kicking issues continued for Myler as he sent another effort wide and right just before the break.
An overzealous Calum Clark was penalised by referee Ian Tempest for hands in the ruck allowing fly-half Swiel, who replaced Evans at half-time, to make it 11-6.
With the contest on a knife edge, Quins tighthead Kyle Sinckler's huge charge gave the home side a prime attacking platform. Several phases later, Swiel's scything pass put flanker Wallace over in the corner. The try was ruled out by TMO David Sainsbury, however, who deemed that Visser had impeded Saints full-back Ahsee Tuala in the lead-up to the score.
Quins continued to ramp up the pressure and were rewarded with another kickable penalty which Swiel converted with ease.
Myler fired over a 65th-minute penalty to take the Saints within a score, but another huge charge from Sinckler put Quins on the front foot once more. Referee Tempest pinged the Saints for offside and Swiel sent over his third penalty to give his side some breathing space. Swiel added a fourth three-pointer in the dying minutes to seal a much-needed victory.