Wasps forwards coach Andy Titterrell says he watched most of his side's win at Saints through his fingers.
It was a nip and tuck encounter at Franklin's Gardens, where the lead changed hands nine times before Wasps eventually won 36-32.
Two yellow cards, which brought a red, for Taqele Naiyaravoro cost holders Saints dear as they suffered a second successive defeat in the Premiership Rugby Cup.
But for Wasps, it was the perfect way to bounce back from the previous week's defeat to Saracens.
"I watched most of the game through my fingers actually, I thought we controlled the game relatively well," Titterrell said.
"First half we had 70 per cent either territory or possession, I don't know the exact figure but it was good to see us playing in the right areas, playing in the corners trying to trust our defence in the set pieces to put pressure on.
"Then obviously tighten things up, we're only two games into the season and have had pretty much two different squads play in two different games.
"I think if we can combine what we had with the set-piece last week against Sarries, with this week's endeavour around the defence and the attack.
"We've still got Sale and Worcester to play before the first league game of the season."
Saints scored five tries in total, but Wasps had the final say with a penalty try after Naiyaravoro's high tackle in the corner.
And Titterrell added: "The attack went well for us again, to score the number of tries we did the second week on the bounce when I think last year we struggled to get over the whitewash, so obviously, that's pleasing to see.
"Defensively, I know we conceded 32 points but the boys put in an incredible amount of work so that got improved from the performance at home and when you're coming away from home anyway even with the side that Northampton picked, you knew they'd come out all guns blazing.
"We questioned certain things about the players after last week about the game and the physicality and obviously they answered some of those."