Dylan Hartley admits Saturday's 'humbling' defeat to Saracens shows Saints are a long way from the standards they need to reach this season.
But the skipper insists he and his team-mates can bridge the gap by the time they take on Leicester Tigers at Franklin's Gardens this weekend.
Both teams will go into Saturday's derby date having lost their opening Aviva Premiership match, with Tigers beaten 27-23 by Bath at Welford Road on Sunday.
Saints endured an even more painful experience as they shipped nine tries in a 55-24 loss to the European champions at Twickenham.
And Hartley said: "You can't give a championship-winning side like Saracens a 40-point head-start. We were playing catch-up from there in the second half.
"There was a lot of frustration at half-time. Obviously Jim (Mallinder) speaks, a few of the on-field leaders speak.
"I think the second half was better, we can take some positives from that.
"But we were chasing four tries in that second half and ultimately with a minute to go, we cough up possession five metres out and we can't take anything from the game. So there's huge frustration from that.
"It's humbling. It certainly keeps you grounded and it shows that we're a long way off where we need to be.
"We had a fantastic pre-season, everyone was positive going into the game but it shows the level we need to be at to compete, and we were a long way off on Saturday.
"There are things to be looked at as to why we had such a slow start and that's what we'll do and build into Leicester this week.
"The nature of this league is that you've always got another big game around the corner and that's exactly what we've got.
"Obviously we're playing at home and we need to put a few things in place and play a proud game at home because certainly on Saturday we were too slow and Leicester are a quality side as well.
"Like I said, we've got things to work on, it's a short turnaround, it's another big game, but we'll be up for it at home."