Boss Gregor Townsend hailed the efforts of his forwards after Glasgow got the better of Saints at Scotstoun.
Former Northampton player Townsend, who turned out at Franklin’s Gardens between 1995 and 1998, masterminded a 27-20 Warriors win on Saturday afternoon.
One of the key factors was the resilience of the Scots’ defence during a first half when they were bombarded by Saints.
The two packs scrapped it out and Glasgow did well to only go in at half-time 10-6 down as they stopped a number of Saints’ set piece moves.
That defiance provided the platform for victory, with Peter Horne’s late try and conversion sealing the four points.
And Townsend said: “I thought the forwards were outstanding.
“We were up against one of the best packs in Europe and we shut down the driving lineout.
“The scrums, in the main, we had parity and at the end we were strong again.
“When we had the ball in the first half we were really good.
“We had it for the first two or three minutes and didn’t see it again for the next 25.
“We had most of the ball in the second half and there are a couple of tries out there we didn’t get.
“It was a great to see that passion and effort in the second half to get the win.”
Glasgow threatened to do something special in the reverse fixture back in October, leading 15-0 at the Gardens before losing 24-15.
They went on to taste defeat in their next four Heineken Cup fixtures before picking up their first and only victory, on Saturday.
Townsend admits it’s been a frustrating campaign, but he was pleased his side finally showed what they could do, against Saints.
“It looked like it was heading towards a draw, which no one likes, but to get a finish like that is a reminder of where we should be, winning games in the Heineken Cup,” he said.
“We have been competitive in games but that’s not what we’re here to do.
“We’re here to win, and that will be a good boost for us.
“We went down to Northampton, who were Premiership leaders at the time, and were 15-0 up so we’ve certainly showed what we can do in patches.
“In the Castres game we were leading for a long time but we just haven’t had the 80-minute performance until now.
“I’d like to focus on the positive feelings I’m feeling, but ultimately it’s not been the season we wanted in Europe.”