Two-time defending European Cup champions Leinster host Clermont in the fourth round of the competition this weekend in the knowledge that they will have to dig deep for a \"vital\" bonus-point victory. Clermont ended the Irish province\'s 17-match unbeaten run in the competition last weekend in a gripping 15-12 win. The French Top 14 outfit\'s victory -- their 51st successive home win -- put them five points clear of the Irish side in Pool 5 ahead of the return fixture in Dublin on Saturday. Leinster manager Guy Easterby said a win for his side was \"vital\", but added: \"I don\'t think the result on Saturday is going to determine who\'s top of the group or who goes through from the group. \"We just see it as a game we have to go out and win,\" the former Ireland scrum-half said, with one eye on the two other clubs in the pool, Exeter and winless Scarlets. \"It\'s not all about topping the group. There are opportunities further down the line. Plus the fact that there are two more games, it\'s not like the pool finishes on Saturday evening. \"We\'ve got a couple of tough fixtures left, as have Clermont, and our group is particularly competitive. \"With the three games we\'ve got left, we\'ve got two at home and one away and we\'ll just be looking to do our best in all of those.\" Easterby added: \"To be so close over there and not get over the line was very disappointing.\" Clermont scrum-half Morgan Parra, who contributed four penalties from four attempts last weekend, said his team could not repeat their showing against Leinster in the competition in 2010, having also been beaten in last season\'s semi-final in Bordeaux. \"We\'ve already had the chance to play this double-header, and after conceding a defensive bonus point at home, we went to Dublin with good intentions before exploding,\" he said of the 24-8 victory by the Irish side. \"We don\'t want to relive that experience. We\'ll need to show that we\'ve made some progress.\" Parra\'s teammate Alexandre Lapandry, who was outstanding on the flank in the first of the double header, added: \"We know what to expect at the Aviva Stadium: they promise us hell. \"But contrary to what one might believe, I hope that we won\'t spend all our time defending because that would be a bad sign,\" he said. \"Instead I hope we\'ll have the chance to keep the ball and won\'t hestitate to take the initiative.\" Leinster\'s Irish rivals Munster beat Saracens 15-9 at home last weekend and now face an equally tricky away return match at Vicarage Road. French giants Toulouse and Toulon, unbeaten in the competition so far, will bid to tie up their respective pools 2 and 6, with matches against Ospreys and Sale. Harlequins and Ulster are also both three from three, and sit firmly in the driving seats of Pools 3 and 4. On Friday, Racing Metro clinched a dogged 15-3 win over Edinburgh to keep their quarter-final hopes alive as last season\'s semi-finalists slumped to a fourth successive defeat. Their win has taken Racing to the top of Pool 1. In the other fixture taking place Friday, Fijian replacement Seremaia Burotu grabbed a last-minute try, converted by Dmitri Yachvili, to give Biarritz a 17-0 home victory over Connacht, avenging their shock defeat in Ireland last weekend. Biarritz currently remain five points behind Pool 3 leaders Harlequins.