Jim Mallinder praised Saints for their management of the sin-bin periods as they saw off Sale Sharks 26-11 at Franklin’s Gardens.
Sale were hampered by Bryn Evans’ first-half yellow card, with Saints scoring twice while the lock, who had got the Sharks’ only try of the game, was off the field.
But when George Pisi was sent for 10 minutes on the sidelines during the second period, Mallinder’s men continued to boss things, refusing to let Sale sneak back into the game.
The victory was Northampton’s fifth in their past six games, and they are now fourth, one point above Leicester Tigers.
“It was an important time for us and, on the flip side, not conceding when we went down to 14,” Mallinder said.
“If they had got within a score it could have got a bit edgy.
“We managed the 10-minute periods well and finished the game well.”
When asked whether he was worried when Saints went 11-0 down, the director of rugby replied: “Yes, and worried after 76 minutes really.
“Sale are a good team, they’re playing really well, they’ve got some good wins, including at Leicester, so we were pleased.
“We were disappointed with the first half, but it was good that we scored just before half-time.
“In the second half, we played pretty well and dominated that period.
“There was some really good play in the second half. Our set-piece work was good and we played some nice attacking rugby.
“In the first half, they slowed us down but in the second half we got some quick ball and moved it away.”
Sale had threatened to spring a surprise, having made six changes to their announced line-up before the game.
And Mallinder said: “I’m not too sure what was going on there.
“I’m sure someone will look at that.
“They must have had a lot of injuries or maybe a bit of food poisoning this morning.”