Rampant Saints record victory
Northampton secured a home semi-final against east midlands rivals Leicester with a record 74-13 win over Wasps.
Jim Mallinder's men were 13-0 down after 15 minutes, but came roaring back with 11 tries - a club record - for their biggest ever Premiership win.
Lee Dickson, George North and Phil Dowson scored two each, with Stephen Myler, Luther Burrell, Ken Pisi, Ben Foden and Tom Stephenson also dotting down.
With a huge points difference advantage over Leicester, Northampton needed just a point to bag a home semi-final, but after 15 minutes that was actually looking in doubt.
Wasps, who had rested a host players ahead of their European Champions Cup play-off match against Stade Francais, got off to the perfect start when Charlie Davies charged down Dickson in the Northampton 22 and picked up to score after just four minutes. Joe Carlisle missed the touchline conversion but added a penalty 10 minutes later.
When Foden's kick was charged down in the 15th minute and Tom Varndell raced over from 40 metres to make it 13-0 a mild sense of panic murmured around Franklin's Gardens.
North got Saints off the mark after Burrell smashed up the middle to suck in the Wasps defence for the ball to be spun wide for the Lions winger to score.
Myler converted and four minutes later the Saints pack drove over from a lineout for captain Dowson to score. Myler missed the conversion, but two minutes later he had his first try of the season.
Foden caught a poor clearance, skipped past two Wasps defenders and popped a pass to the on-rushing Myler to sprint over from 20 metres to make it three tries in seven minutes. With an easy conversion Saints could breathe easy again as they went 19-13 in front to take control.
Myler made it 22-13 before Wasps' giant No 8 Nathan Hughes was sin-binned for being offside at a ruck.
Saints immediately took advantage with Pisi catching Tommy Bell in two minds over Myler's grubber, but the TMO ruled he failed to ground it.
A minute later Mike Haywood burst onto Dickson's pop pass and sent Burrell over with a perfectly timed pass.
Three minutes after the break Saints' dominant scrum drove over allowing Dickson to dot down. Myler converted and Wasps began to cave.
James Wilson was held up over the line but from the resulting scrum, which saw the return of Lions loosehead Alex Corbisiero after six months on the sidelines, Foden nipped over.
Wilson, with Myler replaced, converted and the new fly-half was almost driven over only for Dickson to rip the ball out for his second.
A rare Wasps attack then ended with a turnover and North racing over from 60 metres for his second to bring up the half-century.
Saints were now queuing up to score and after Pisi dotted down things were made even easier with six minutes left when Wasps skipper Chris Bell was sin-binned for a tip-tackle on Wilson.
It allowed Stephenson and Dowson to add two more tries and make it Wasps' heaviest ever Premiership defeat.