Sale boss Steve Diamond gave credit to Saints after his side secured victory at the AJ Bell Stadium on Saturday afternoon.
Denny Solomona touched down twice as the Sharks came away with an 18-13 triumph, but they failed to take the other chances which came their way.
They next face Bath in the Gallagher Premiership and Diamond is looking for his players to be far better when the opportunities present themselves.
"I'm not pleased with the performance if I'm honest," Diamond said.
"I'm pleased with the result, but I thought Northampton looked after us pretty well.
"We created a lot of chances but we just couldn't get there in the end with maybe five or six other opportunities.
"We had some ball and managed to eke out a win in the end.
"It's about finishing the chances off. If Luke James can pass to Arron Reed, it's a run-in in the corner.
"I thought Northampton were very good on the floor, they slowed a lot of ball down.
"There were three line breaks where they were allowed to slow the ball down, which we will have a look at and have a chat with the referees about it."