Ireland coach Joe Schmidt has made three changes to his starting XV to play France on Sunday in a World Cup match that will decide who tops Pool D and avoids New Zealand in the quarter-finals.
Following a gritty 16-9 win over Italy, having easily beaten Canada (50-5) and Romania (44-10), Ireland face a must-win game against the similarly unbeaten French. The pool winners are likely to get an easier task against Argentina.
Schmidt replaced stand-out lock Iain Henderson with Devin Toner, while Rob Kearney comes in for Simon Zebo at full-back and Cian Healy takes over from Jack McGrath at loose-head prop.
"We understand that there's pressure," Schmidt said, insisting that that was what the squad thrived on.
"The players respond really well to that pressure, there's a strong core of leadership in the group, I'd they're conscious of the pressure, but more excited by the challenge."
Schmidt said it was a "really tight call" to omit Henderson for Toner.
"'Dev' has been a big match player for us, he has done really well, he gives us a little bit more lineout capability and we do believe that at the back end of the game Iain will add value," the New Zealander coach said, with Henderson likely to cover blindside flanker as well as second row.
"Again we're trying to make sure that we've got a few things covered for next week as well so it's a bit of a balancing act at the moment.
"Having qualified, but being very keen to qualify at the top of pool and at the same time knowing the reality that regardless of where you finish in the pool you're going to have to play next week with a side that's incredibly well capable because either of the opposition we'd run into will be very, very difficult."
Connor Murray and Jonny Sexton continue at half-back, with Robbie Henshaw and Keith Earls continuing their midfield partnership, Tommy Bowe and Dave Kearney lining up on the two wings.
Paul O'Connell will skipper the team from lock, packing down behind Healy, veteran hooker Rory Best and tight-head Mike Ross.
A strong backrow sees Jamie Heaslip at No 8 between Sean O'Brien and Peter O'Mahoney.
South African-born hooker Richardt Strauss comes in to the replacements' bench as frontrow cover alongside McGrath and Nathan White, with Henderson and Chris Henry providing further forward cover. Eoin Reddan, Ian Madigan and Luke Fitzgerald complete the bench.
"We believe midfield's going to be quite attritional," Schmidt said in way of justifying the fleet-footed Zebo's absence from the match-day 23. "We think that's going to be a really tough day at the office.
"Luke Fitzgerald covers that as well as the back three so his versatility is an asset for us there."
Ireland team (15-1) to play France in World Cup Pool D decider at Cardiff's Millennium Stadium on Sunday (kick-off 1545 GMT):
Rob Kearney; Tommy Bowe, Keith Earls, Robbie Henshaw, Dave Kearney; Jonny Sexton, Conor Murray; Jamie Heaslip, Sean O'Brien, Peter O'Mahony; Paul O'Connell (capt), Devin Toner; Mike Ross, Rory Best, Cian Healy
Replacements: Richardt Strauss, Jack McGrath, Nathan White, Iain Henderson, Chris Henry, Eoin Reddan, Ian Madigan, Luke Fitzgerald
Coach: Joe Schmidt (NZL)
Source: AFP