The Saints have been drawn alongside the reigning Pro 12 and Amlin Challenge Cup champions, Leinster, in what will be a re-match of the 2011 Heineken Cup final.
But while the Anglo-Irish clashes may grab the headlines, the Saints will also be facing two other teams with considerable pedigree.
The Ospreys have won the Pro 12 title twice in the last four years and provided a third of the Welsh national team which beat England to win the 2013 Six Nations, while Castres confirmed their progress over the past few years by overcoming star-studded Toulon to win the Top 14 for the first time in 20 years last Saturday.
"It's a very tough draw for us, alongside the reigning Pro 12 and Top 14 champions," Mallinder commented. "Leinster have proved time and again over the past few years that they are one of the top teams in European rugby, with plenty of strength in depth and the ability to play well in the biggest occasions.
"The Ospreys are another top team who have won the Pro 12 twice in the last four years. They have five British Lions in their squad and plenty more Welsh internationals, and Anglo-Welsh clashes in the Heineken Cup are always hard-fought.
"Meanwhile we know that Castres will be as tough as they come. In previous years they have been a difficult team to play, and they will go into next season full of confidence after beating both Clermont Auvergne and Toulon on the way to winning the Top 14 title.
"All six of the matches will be tough challenges, but we will be looking forward to all of them and trying our hardest to get into the knockout stages."
As in previous years the Saints will be running trips to all three Heineken Cup destinations. So whether you want to travel to Dublin, Swansea or the south of France, email [email protected] to register your interest.
The three Heineken Cup games are also included in the 2013/14 Season Ticket package - for more information visitwww.northamptonsaints.co.uk/tickets
FACTS AND FIGURES
- Although they went head-to-head in the 2011 Heineken Cup final, the Saints and Leinster have not met in the pool stages of the competition since 2000/01
- Between them, Leinster and Ospreys provided 11 players to the 2013 British and Irish Lions squad - just under a third of Warren Gatland's touring party
- The Saints and Ospreys have never met in the Heineken Cup
- However the Saints and Ospreys have come up against each other in two out of the last four LV= Cups; in both years the Saints went on to the final