Saints boss Jim Mallinder praised his players for pushing Leicester Tigers all the way in the 22-14 defeat at Welford Road.
Mallinder made 12 changes to his side with top spot in the Aviva Premiership already secured.
And the men who came in made their mark moving into a 9-8 lead at half-time before eventually succumbing during the second half.
Quickfire yellow cards for Gareth Denman and Salesi Ma’afu proved costly as Tigers turned up the heat in the scrum, but Saints emerged with credit.
And Mallinder, who saw James Wilson notch three penalties and Tom Stephenson score a try, said: “It was a good effort. We pushed them and went in ahead at half-time.
“We said we needed to keep playing and hopefully the crowd might start turning a little bit.
“Unfortunately, Leicester had a very strong 10 minutes where they squeezed us in the scrum and that made the difference.”
Leicester’s win means they will now go to Bath in next Saturday’s Premiership play-off semi-final.
Saints will host Saracens on the same day (2pm kick-off).