The Official Online RBS 6 Nations Store is open. The store has everything you need to get behind your team during the RBS 6 Nations, plus the store is now fully stocked with a much wider range of rugby merchandise.
There was also bad blood between the two clubs over prop Soane Tonga'uiha's move from Northampton to Watford before his sensational u-turn.
The Saints are protecting the only perfect record in the Aviva Premiership this season after storming to victory against all of last seasons' top four contenders.
But the cruel 21-19 stoppage time defeat after Glen Jackson converted Schalk Brits video replay awarded try still lingers long in the memory of Mallinder.
Mallinder, who is set to be without England winger Chris Ashton, said: "There is extra motivation to beat them after losing that semi-final.
"It was a bitter blow to us, without a doubt. We had done well at Franklin's Gardens but then we lost two games in a short period of time and with it the chance of going to Twickenham.
"That is still fresh in our memory and it is something that we want to put right.
"If we can get a win at the weekend, it would be a good statement to the rest of the Premiership in terms of where we are."
In Saturday's matches, London Irish will be aiming to pile the pressure on Saints but they travel to Newcastle without Steffon Armitage as the England flanker is sidelined for six weeks after fracturing his right shin last week.
Will Skinner and Chris Robshaw make their 100th appearances for Harlequins against newly promoted Exeter, who hope to maintain their impressive start to life in the Premiership.
Two sides who have hit the ground running this season clash as Bath entertain Sale, who make two positional team changes with Wales international Dwayne Peel starting at scrum-half.
Leicester Tigers seek to kick-start their season against struggling Leeds Carnegie while Wasps will strive to build on their first win of the season against the Tigers, with a trip to Gloucester.