Cobus Reinach says Alan Gaffney's arrival has been crucial in lifting Saints' confidence levels.
Gaffney has been drafted in as coaching consultant on a contract until the end of the season, and the Australian has seen his new side win both of their games under his guidance.
Saints beat Gloucester in their first match of 2018 and backed that up with a brilliant 34-21 Champions Cup success against Clermont Auvergne on Saturday evening.
Those back-to-back victories at Franklin's Gardens have got the monkey off the back of the players, who had suffered 12 defeats from 13 matches at the end of 2017.
And when asked how key Gaffney's appointment has been, Reinach, who scored the fifth and final try against Clermont, replied: "Very important.
"He came in and focused on a lot of the little things: running straight, passing in front of the guy.
"All the little things we got wrong we're trying to rectify now.
"It's easy to see in the bigger picture that the little things are working."
Gaffney has told Saints they need to work harder - and the players have responded.
"We talk about getting back in the game, working hard and reloading," Reinach said.
"It shows if you're working hard and we're all accountable for the effort we put in."