Hartley - Saints have learned from opening day "hiding"
Northampton Saints captain Dylan Hartley believes their humbling defeat to Saracens on the opening day of the Premiership season was a "good wake-up call" as the teams prepare to meet again in the Champions Cup on Sunday.
Sarries ran in nine tries, including seven in the first half, to win 55-24 at Twickenham - but since then Saints have responded with four wins in five league games.
The two Premiership clubs will now go head-to-head at Franklins Gardens as Saracens begin the defence of their title and look to win the Champions Cup for an unprecedented third successive season.
But Hartley believes Northampton are now better prepared to counter the challenge posed by Europe's top team, after the "hiding" they received last month.
"When you play against European champions at Twickenham, big sense of occasion and the majority of your team don't turn up mentally and physically you're never going to win those games.
"We've gone away, revisited a few key things - physicality in rugby, there's no point even playing the game if you'er not going to be physical - it's a contact sport. So that's something we've really hung our hat on, we've been focusing on in our training week and going into a game."
Northampton and Saracens are joined in Pool 2 by French club Clermont Auvergne and Welsh side Ospreys.