Northampton boss Jim Mallinder hailed his team's composure after they fought back from a 15-point deficit to topple Heineken Cup opponents Glasgow 24-15 at Franklin's Gardens.
A Pool Four shock looked likely when Glasgow raced into a 15-0 lead courtesy of tries by flanker Josh Strauss and wing Sean Lamont. But Northampton recovered to score three tries in six minutes either side of half-time - George Pisi (2) and Stephen Myler the beneficiaries - before wing Vasily Artemyev's late score secured an unlikely bonus point victory.
"We were under a bit of pressure, but what was pleasing was the way we came back and kept our composure. In the second half, we controlled the game," Mallinder said. "It could have gone a different way, and what you cannot do is underestimate sides in the Heineken Cup. We didn't do that - Glasgow are a quality team."
He added: "They have a big heavy pack with a back-row that gets around the field and backs that can take their chances.
"I think we are in decent shape. When we are on top of our game we are a hard side to beat, and we need to keep at that intensity every single week."
Saints now have just a five-day turnaround before tackling Castres in Toulouse next Friday night, with Glasgow in the same boat before hosting Ulster.
Mallinder added: "I don't think it is quite right that Castres have got seven days to recover from their game two days ago, and we've got just five and having to travel to France as well, but that is the way it is.
"It is always a massive challenge playing in France, but if we play at the top of our game then we've got a good chance of winning."
Mallinder admitted that memories were evoked of last season's poor European campaign when Glasgow took the early initiative.
"The Scarlets came here last season and turned us over, which started our Heineken Cup season badly, and we never really recovered," he said. "But we didn't panic today and there were positive messages out there on the pitch."