Another victory for Montpellier over the Blues would keep the pressure on their French rivals, who already look favourites to qualify for the knockout stages of the tournament.
Fabien Galthie's Montpellier could still have a major impact in whether Jonny Wilkinson's Toulon get the all-important home quarter-final in the next three rounds of this Pool.
The Cardiff Blues, who played with 14-men for most of the first leg defeat to Montpellier, will be looking to keep all their players on the field for the return fixture in France.
The Welsh region produced a creditable performance against Montpellier, after scrum-half Lloyd Williams was red-carded, but they are still looking for their first win in this season's tournament.
• Alex Cuthbert is the joint-top try-scorer in the Heineken Cup with three touch downs so far, all of which came in their opening game at Sale.
• Collectively, Cardiff Blues have missed the most tackles in the tournament so far. Three Cardiff players (Josh Navidi, Lou Reed and Marc Breeze) are first, second and joint-third respectively on top of the missed tackles list.
• Montpellier are the only team in the tournament to have won every scrum they have had the feed at.
• Should Cardiff lose this game, it would be their worst run in the tournament since they lost five in a row in 2004/05.