Jim Mallinder admitted Saints’ showing in Friday night’s defeat to Wasps was ‘unacceptable’.
Mallinder’s men slumped to a 24-11 loss after three tries in the opening 30 minutes of the match left them with a mountain to climb.
And they failed to scale it, with only Sam Dickinson’s late score providing any reason to smile for the home fans at Franklin’s Gardens.
Dan Robson, Rob Miller and Josh Bassett all dotted down for Wasps before the half hour mark, with Saints heading off to a few boos at half-time.
They struggled to summon a response in the second period, even when Wasps had Nathan Hughes in the sin bin, and Mallinder was far from happy with the display.
“We were hoping we’d turned a bit of a corner in Europe,” said Mallinder, who had seen his side win back-to-back Champions Cup games in the previous two weeks.
“We’d put in two good performances, scored some good tries and we needed to back it up.
“But that first half was unacceptable, our defence was poor, we had no linespeed whatsoever, we couldn’t get our set piece functioning at all, so we gave our backs nothing to work from.
“Just generally we looked flat as a team. We made a couple of changes, as did they. You come off a couple of games in Europe and you look to freshen things up, but clearly their changes worked better than ours.”