Connacht's Jack Carty is well used to changeable weather and all that time spent in the lashing rain of Galway may just work out for Ireland.

Joe Schmidt's men face Scotland on Sunday morning in their World Cup opener with torrential rain forecast in Yokohama.

Johnny Sexton will start at out-half and while second-choice Joey Carbery, injured against Italy in August, trained fully today, it may be the 27-year-old who gets the nod for the replacements bench.

If so he will have left no stone unturned when it comes to goal-kicking with sports psychologist Enda McNulty helping him out at training.

Carty outlined some of the routines.

"I was doing a few kick reps with Enda McNulty and he was putting scenarios in my head," he said.

"[He's] putting pressure on you when you are taking kicks

"When you are lining up a kick he might say, '66th minute' or 'howling wind' and he'll come over and kick the ball off the tee.

"So it's about not trying to get too annoyed with him for that, trying to stay cool and calm and then go through the process again that you've already done because he's kicked the ball off the tee.

Jack Carty speaks to the media

"That's quite beneficial. I find it works.

"If that does come up you tap into the back of your head that you've already done it.

"It's been a bit strange, two days ago it was really warm [in the training base at Chiba]. I got scalded and today it's raining so it's a bit like Galway.

"He actually said [if you can do it in the Sportsground you can do it anywhere], so touch wood it will all go well.

"It's pretty similar to what I've been used to in Galway. It was quite windy and wet where we were.

"I suppose it's nice to have had those conditions regularly throughout the year so whether it's [bad weather] as it looks to be over the weekend or if it's drier and humid we've had our warm-weather conditioning in Portugal so I think we're well prepped."

Robbie Henshaw is currently injured

Carty's former provincial team-mate Robbie Henshaw suffered a hamstring injury in training and is rated highly unlikely to feature against Gregor Townsend's side.

But the seven-times capped Roscommon man backed the Leinster centre to recover.

"You could see the energy Robbie brought last week against Wales, especially in defence," he said.

"For him it's obviously a bit of a blow but if you look at the three lads that are there [Bundee Aki, Garry Ringrose, Chris Farrell], they bring their own things to the pitch and when they are at their best they are world class.

"It's obviously bitterly disappointing for Robbie. He'll be working hard to get back."

Follow Ireland v Scotland on Sunday (kick-off 8.45am) via the live blog on RTÉ.ie/Sport and  the News  Now  App, watch live on RTÉ2 from 8am or listen to live match commentary on RTÉ Radio 1.