Wasps crashed to a second home defeat in succession as resurgent Northampton won 22-17 to collect a third consecutive Gallagher Premiership win.
After last week’s 49-17 thumping at the hands of an impressive Harlequins, Wasps must have expected a better performance but poor decision making and ill-discipline in the first half cost them dear.
At the interval the hosts trailed 22-0 and although they were a rejuvenated side in the second half they could not claw back the substantial deficit.
Northampton’s tries came from Shaun Adendorff, Sam Matavesi and Taqele Naiyaravoro with James Grayson kicking a penalty and two conversions.
Rob Miller and Tommy Taylor scored Wasps’ tries. Jimmy Gopperth converted one with Jacob Umaga adding a penalty and a conversion.
Northampton made the better start and took a 13th-minute lead when Grayson kicked a straightforward penalty.
In response Wasps built up their first period of pressure and were awarded three easily kickable penalties. Each time they opted to seek the reward of a try and it proved the wrong decision as they could not capitalise with the award of a scrum penalty allowing the visitors to relieve the onslaught.
Saints immediately made them pay by scoring the first try. After a strong touchline run from Ollie Sleightholme put the Wasps defence on the back foot, number eight Adendorff was up in support to force his way over for his third try in two games.
Worse was to follow for the home side when they lost two forwards in quick succession to the sin-bin. First was prop Kieran Brookes, for carelessly charging into a ruck swiftly followed by lock, James Gaskell, for an off-the-ball challenge.
Reduced to 13 players, Wasps had no way of stopping a formidable 25-metre line-out drive from Saints which culminated in Matavesi crashing over.
Grayson converted before Saints scored their third when Naiyaravoro forced his way over from close range with another conversion from Grayson giving his side a 22-0 interval lead.
Within three minutes of the restart, Wasps produced their first flowing movement of the game and it paid dividends as Miller picked up their first points with an excellent try.
The hosts received further encouragement when Naiyaravoro was yellow-carded for a high tackle but they suffered an injury setback when replacement prop Simon McIntyre was led off with a leg injury only a minute after coming onto the field.
Naiyaravoro returned from the sin-bin with no damage done to the scoreboard but Wasps came back into contention with a penalty from the recently introduced Umaga.
Northampton centre Piers Francis was yellow-carded for a deliberate offside for Wasps to immediately benefit with a try from Taylor, which was converted by Umaga, but that was as close as the hosts could get.
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