Northampton secured back-to-back wins in all competitions for the first time since September as they inflicted a first Champions Cup defeat of the season on Clermont Auvergne.
Saints -- already out of Europe following four straight defeats -- ran in five tries courtesy of Teimana Harrison, Nafi Tuitavake, Ben Foden, Ken Pisi and Cobus Reinach in a 34-21 victory at a buzzing Franklin's Gardens.
The loss for Clermont, last season's runners-up, also means they must wait until next weekend to secure qualification for the knockout stages.
It had been plain sailing for Clermont in this competition to date with four wins from four putting them in pole position to reach the last eight for another year.
But despite an early effort from Remy Grosso and an Isaia Toeava try, plus the boot of France international Morgan Parra, Clermont were still unable to return to winning ways.
The French giants entered this clash against a Saints side -- still finding their feet since Jim Mallinder's December sacking -- on the back of three straight Top14 defeats.
Restoring pride was the target for the Alan Gaffney's Saints who made three changes from the dramatic victory against Gloucester last weekend.
Tom Stephenson was in for the injured Luther Burrell with Kieran Brookes and Christian Day bolstering the pack.
It was the visitors who came out of the blocks quickest and went ahead inside two minutes. Wing Grosso was the man to touch down as he powered his way over in the corner with Parra mastering the conversion from the touchline.
The Saints soon settled and found a response on 13 minutes with number eight Harrison touching down in the corner following a surging break from lock Api Ratuniyarawa but Harry Mallinder could not land the conversion.
Clermont extended their lead through full-back Toeava's try and a Parra penalty on 31 minutes. But Northampton battled back before the break when Tuitavake sped through unscathed with his first touch of the ball after replacing the injured Ahsee Tuala.
After the interval, the hosts went into overdrive. First Mallinder kicked a penalty in off the post before wing Foden blitzed his way through out wide. This time fly-half Mallinder was spot on with the extra two points.
Parra hoisted Clermont back ahead with two penalties, while Mallinder could not convert a kickable opportunity to restore the hosts' lead.
But the miss did not matter when Pisi scored the bonus-point try and the inconsistent Mallinder drilled the conversion for a six-point advantage with 15 minutes to play.
Replacement Reinach put the seal on things on 73 minutes -- powerfully punching over -- as Mallinder kicked the conversion to well and truly rub salt in the wounds of Clermont.
It means Gaffney has now won both of his two games in caretaker charge, the veteran coach making an early case to take on the job full-time for next season, should he want it.