Ireland have no concerns about potentially thrusting Test rookie Jimmy O’Brien into a World Cup quarter-final against New Zealand as they anxiously wait on the availability of first-choice wings Mack Hansen and James Lowe.

Hansen was forced off for a head injury assessment in the first half of Saturday evening’s 36-14 win over Scotland before suffering a calf issue on his return.

Lowe departed at half-time due to a bang in the eye after claiming the first of his side’s six tries in Paris.

Versatile back O’Brien, who made his international debut last autumn, is the only member of Andy Farrell’s 33-man squad yet to feature in France and has started just four Tests across seven caps.

The 26-year-old may well be needed against the All Blacks as, in addition to the fitness concerns for Lowe and Hansen, veteran wing Keith Earls is nursing a slight hamstring problem.

Defence coach Simon Easterby said: “It’s probably a little too early to say either way but, if they get ruled out, Jimmy’s been waiting in the wings and did an incredible job last November to come in with a couple of late call-ups.

“There’s no issue with Jimmy if he gets an opportunity. Hopefully we’ll have a full deck to choose from come Tuesday or Wednesday.

“It’s mad when there’s a late kick-off, we’re getting used to them, but it takes a bit of time for injuries to settle and then for guys to get assessed.

“In the next 24 to 48 hours we’ll be able to get a better read on those guys, but everyone’s in good form today, which is nice.”

Centre Garry Ringrose and scrum-half Jamison Gibson-Park were deployed as makeshift wide men in the second period at Stade de France as Ireland breezed into the knockout rounds while eliminating the Scots.

Earls was absent from the matchday 23 along with centre Robbie Henshaw, who also has a hamstring problem.

“It’s one of those things that at a push he could have been involved this weekend, and it was probably one of those we felt wasn’t the right time to risk him,” Easterby said of Earls.

“But we were really pleased it was flagged when it was and we had the opportunity to make the call early enough.

“Fingers crossed he’s fully fit for this week.

“They’ll both be running today, Earlsy and Robbie, and will sort of be progressing into training Monday or Tuesday.”

Lock James Ryan, who injured his other wrist after sustaining a similar issue against South Africa a fortnight ago, is another player being assessed.

Ireland are preparing to face the “standard bearers of the World Cup” after topping Pool B thanks to four consecutive wins.

Three-time champions New Zealand defeated Joe Schmidt’s Ireland 46-14 in the quarter-finals of the 2019 tournament in Japan.

The All Blacks have extensive inside knowledge of Farrell’s men due to Schmidt joining their coaching set-up ahead of Ireland’s series success in New Zealand last summer.

“I’m sure Joe’s influence certainly has increased in the past 12 months, but we’ve got to be excited about playing the standard bearers of the World Cup,” said Easterby.

“Certainly Joe will know plenty about what we’re about, the individuals within our group, but we’ll have an insight as well into what they might try and do as well.

“So I think it’s finely balanced and it’s an interesting sub-plot to the game itself.”