Ireland forwards coach Simon Easterby has backed Jordi Murphy to be a success at this World Cup but Chris Farrell is already ruled out of the clash with Russia on Thursday (11.15 UK time).
Ulsterman Murphy arrived in Japan yesterday as a replacement for the injured Jack Conan having been a late cut when the 31-man squad set off earlier this month. He had previously been pulled from PRO14 duty on Friday night, the confirmation of his call-up coming only after the shock 19-12 defeat to Japan in Shizuoka on Saturday.
The 28-year-old, who will be playing at his second World Cup, is likely to come straight into the side for Russia that Joe Schmidt will name tomorrow morning.
"We are very fortunate that Jordi Murphy will be joining us," said Easterby.
"He gives us great coverage, he's been in the squad for a number of years and he has played in some big games.
"He can cover every position in the back-row, which obviously gives us a good deal of flexibility across that back-row with things starting to ramp up a little bit.
"As we go through the tournament guys will pick up bumps and niggles. It's great to have Jordi coming in and he'll slot straight in this week."
Farrell, who came off the bench in the win over Scotland before starting against Japan, however sustained a concussion at the weekend and will miss out against Russia.
With Robbie Henshaw yet to feature at this tournament, Schmidt may have no choice but to pair Garry Ringrose and Bundee Aki in his midfield once again, although Leinster’s Jordan Larmour featured there off the bench on Saturday.
Elsewhere, Johnny Sexton is expected to start having missed the pool-altering defeat with a quad complaint.
“I suppose the only blessing in disguise is that, in the last two World Cups that I’ve been involved in, we’ve not cruised through the group, but we’ve had everything go our way in the pool stages,” said Sexton.
“And then we’ve had the day that we had yesterday in a quarter-final and we’d be going home today.
“The great thing now is that we’ve got the rest of the pool to get things together. We know, to a certain extent, that we’ve got things in our own hands in terms of if we can win the last two games and score a number of tries we can definitely qualify for the quarter-final.
“If that’s in first or second place, that’s out of our control, so we won’t worry about that. That’s done now. So it’s up to us now to put in two big performances and hopefully put ourselves into a quarter-final and, we know if we do that then we’ve got a chance.”