Jim Mallinder was left to rue Saints' lack of defensive desire as they shipped seven tries in a 46-31 defeat at Newcastle Falcons.
It was a sobering Sunday afternoon for Mallinder's men, who saw a 24-15 half-time lead slip, conceding five times after the break.
The heavy defeat pushed Saints down to eighth in the Aviva Premiership standings, with the Falcons flying up to seventh.
And Mallinder stressed his disappointment in his team's inability to shut opposition sides out after a second successive league loss.
"It was a little bit of everything," said the Saints boss when asked what went wrong for his team in Newcastle.
"In defence, you need the desire, you need to want to bring players down and we were a little bit loose.
"Some of our kicking wasn't the best, some of our option taking wasn't the best and we just didn't close them down enough.
"We did have opportunities to tackle them, but we didn't take them."
Saints did manage to claim a try bonus point thanks to efforts from Ken Pisi, Jamie Gibson, Harry Mallinder and Mike Haywood.
But it was barely any consolation on a horrible afternoon in the north east.
"It was a poor second half," Mallinder added.
"We talked about controlling the ball, we know about their dangerous runners and on a surface like that, you can't give their wingers any space and time.
"Particularly in that first 20 minutes of the second half, we were terrible, loose and just not putting the tackles in as well.
"When that happens, Newcastle are a good side and can clearly score tries."