Castres away can earn home comforts for Leinster
Cullen's men prepared for tough French test
This is the third time in four seasons that the schedule has brought Leinster to Castres, and the Irish province have always found life difficult in this particular corner of France.
Matt O'Connor's team managed a seven-point win on their first visit of 2014, and when they returned later that year the deficit was down to four. Neither was easily achieved.
Leo Cullen came off the bench on the first occasion and was in the coaching box the second, so is fully aware of what awaits his side as they look to secure their place a-top the ladder of Champions Cup quarter-finalists with a bonus-point win.
Any sort of victory will earn them a home quarter-final, but the higher they can get up the final standings the better ahead of the draw. Win, and they can sit back for the weekend and watch the rest scramble for position.
A year ago, Cullen's side went down to a record defeat at Wasps having long ceased to have any tangible interest in the tournament, so to come back so strong is mightily impressive.
Bringing knock-out rugby to Dublin will boost the coffers and can kick-start a new era of success after a relatively fallow two seasons.
It will help that Castres are effectively out of the tournament despite the remote mathematical chance that they can still reach the quarter-final.
Their coach Christophe Urios makes nine changes from the 28-21 defeat away to Northampton Saints. He still has quality in the ranks, but they have little to play for.
Castres, however, are one of those French sides who pitch up at home no matter what. They have an eight-day turnaround until their next game at home to Montpellier so can have a cut and know there is plenty of recovery time.
Their record at the Stade Pierre Antoine is excellent - they last lost there on September 3 - and they sit sixth in the Top 14. They are a dangerous proposition for Cullen, whose main fear must be how well his side will cope when they get a full and proper test.
Their last three European games have been walks in the park and, while they are looking like a really impressive unit who blew away a strong-on-paper Montpellier side last week, the standard of the opposition performances has not been of the highest level. Perhaps a tough test in the south of France is exactly what the doctor ordered.
Certainly, Adam Byrne and Rory O'Loughlin will benefit from the experience as they retain their places on the wings despite Rob Kearney's presence on the bench, while Jack Conan is another who can show once again just how good he is in Sean O'Brien's absence.
Ross Molony gets the nod to replace the banned Hayden Triggs, with the experienced Mike McCarthy on the bench. Richardt Strauss replaces James Tracy as Cullen rotates two of his three front-rows, with Cian Healy chomping at the bit to take his chance as a starter after coming in for Jack McGrath.
Cullen warned of the threat of the Castres scrum, but last week's sparkling display against Montpellier showed the way.
"We want to play a high-paced game and impose our game, but we need to have the accuracy because they're very comfortable without structure," the head coach said.
"It is that mix of just being accurate when we get the ball so we don't give them life and energy into the game.
"When they get on a roll, they are a dangerous team to stop. They've scored a lot of points, especially at home."
If Leinster can hit those levels on a consistent basis, then the good times really will be back.
The key tonight will be front-foot ball. O'Brien's calf injury keeps him out and must be a slight concern to Joe Schmidt given the proximity of the Six Nations, so Conan will be asked to pick up the slack.
After his impressive performance against Montpellier, Luke McGrath may not get quite such an armchair ride but good, clean ball will allow the Sandymount native the opportunity to release a backline that is looking slicker by the week.
The bookies have Leinster as 13-point favourites to wrap things up with a win, but Cullen is wary.
"They're are a proud club," he said of the hosts. "They don't have the same resources or budgets as some of the other Top 14 teams but year after year they have always punched above their weight - they always stay in and around the top six. At home they are very strong.
"They won the Top 14 four or five years ago, reached another final as well. They have a reasonably new coaching group, went through a sticky patch but have come out the other side of it.
"They are a well-coached team, comfortable playing a non-structured game.
"They don't have the same size and power as some of the other Top 14 teams so they have adjusted their game slightly. They have had wins over Toulon, Racing and Montpellier this year at home. It is going to be a tough challenge for us."
Given the mediocrity produced by the third best team in the French league this season at the RDS last weekend, it is difficult to get to worked up over French opposition, even if they normally do play better at home.
The prize is too great for Leinster to let it slip now.
A home quarter-final and potential top-seeding beckons, and they're good enough to take it.
CASTRES - P Berard; J Caminati, A Taumoepeau, F Vialelle, D Smith; J Dumora, A Dupont; A Tichit, B Mach, D Kotze; V Moreaux, R Capo Ortega (capt); Y Caballero, A Bias, S Mafi. Reps: J Jenneker, M Lazar, D Tussac, L Jacquet, A Jelonch, J Seron, B Urdapilleta, T Cambezou.
LEINSTER - I Nacewa (capt); A Byrne, G Ringrose, R Henshaw, R O'Loughlin; J Sexton, L McGrath; C Healy, R Strauss, T Furlong; R Molony, D Toner; J Conan, J van der Flier, J Heaslip. Reps: J Tracy, J McGrath, M Bent, M McCarthy, D Leavy, J Gibson-Park, R Byrne, R Kearney.
Ref - G Garner (RFU)
Castres v Leinster,
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