WP Nel is the shape of a boulder and is just as hard to move, not so much in a physical sense, but in an emotional sense.

We are now at the point where players at this World Cup have been away from home for so long that some of them may be forgetting what normal life really feels like. Take Nel, for instance. He's got a wife and three kids back in Edinburgh. Henre is nine and will turn 10 next week. That's a birthday he's missing.

Then there's Arabella who is five and Kayla, the baby, only born in the middle of July. Not that he would want to consider this for too long but if Nel added the number of days wee Kayla has been in this world and subtracted the number of days he's been in training camps or out here in Japan then the reality is that he's been away from her for half her life.

So while we probe about the loss to Ireland and the damage it wreaked and the victory over Samoa and the relief it brought and the upcoming must-win games against Russia and against Japan, there is something else that's relevant in all of this and that's the psychological battle the fathers of young kids go through while living in this rugby cocoon.

Nel was asked about this on Friday. It's fair to say that he didn't exactly break down in tears at the mention of his absent family, but that's not to say that this stuff isn't another thing professional rugby players have to handle. It is. Some might be out of form or out of favour or missing home, but they still have to deal with those emotions like they don't exist. No visible signs of gloominess are encouraged in this environment.

"The mental battle is always there," he says. "You miss your family, you want them around you, but as a team we are close together and we are helping each other. Sometimes phone calls home can be difficult. The kids are getting emotional, it's getting long (the time away) but it's our job. Back home, even if you are a weekend away its tough for the kids. They don't like it, but you somehow need to get around it. It's part of the game. That's why you're playing - for the family and for the team around you.

"The next game is on Wednesday so they'll (Henre and Arabella) probably be in school. The Samoa was game on Monday but I know my boy will probably have watched it about 10 times by now, he will probably say to me what I did wrong.

"I'll need to bring them back presents. I need to empty my cases and put some stuff in there. I have got the list on my phone, a big list. It's all the way from cars to dolls."

Nel can't allow himself to dream about home just yet, not when we are now in the heart of the tournament from a Scotland perspective. Two pool games played, two pool games left. Russia first.

Russia getting 'better and better'

"With every game they have got better and better," says Nel of a side coached by the Welsh veteran Lyn Jones. "The have a good forward pack. If you see how they prepared they were for Ireland then you know that they are a well coached side and we need to be ready for them and we need to take our game plan and execute it. Their tighthead (Kirill Gotovtsev, who has also represented Russia in wrestling and bobsleigh) is playing well and is the anchor of the scrum. You can see that everything revolves around him at scrum-time. He will be a big factor for us in our preparation."

The rugby world is counting the days to Scotland playing Japan in what could be one of the most dramatic days in this tournament.

The first wave of Japanese journalists turned up at Scotland's press conference on Friday. Wave after wave will follow. They continue to carry with them an absolute reverence for Greig Laidlaw, as if he's some kind of modern day amalgam of Gareth Edwards, Nick Farr-Jones and Joost van der Westhuizen.

The fixation that dates four years to when the scrum-half starred against Japan in the last World Cup and then carried on in the summer of 2016 when Japan were looking like they might beat the Scots in Tokyo only for Laidlaw to come off the bench to save the day.

Before they both go to Yokohama there's business to be done. Russia will be surely be put away with a bonus point in Shizuoka but the evidence so far is that they'll take a bit of breaking down before the tries come. On the opening night of the World Cup, Japan only claimed their all-important fourth try against the Russians in the 68th minute. Jones's team were then dealt some cruel blows, literally, against Samoa who had two players sin-binned in the first half when it's now been acknowledged that the pair of them should have been sent-off. What a difference it may have made to the final score had Russia been playing against 13 men for more than 40 minutes.

Even against Ireland, they denied them a bonus point score until the 61st minute. They'd held the Irish scoreless for 25 minutes at that point. They shipped five tries and 35 points in the end, but they frustrated Joe Schmidt's team no end. Russia couldn't score, but they never stopped battling.

Scotland's forwards coach, Danny Wilson, is a Welshman and knows Jones well. "Russia are a very good defensive team, their contact area defence is a real handful," says Wilson. "Lyn will be heavily involved in that.

"They have grown throughout the tournament and we'll have to be right on top of our game to deal with that. Lyn is a very clever coach. We did a lot of our coach education at the same time and he's one of the brains of the game in my opinion. I'm sure he'll have something up his sleeve.

"At times they frustrated Ireland and I think they turned them over eight times, and five of those were around the breakdown. So we know what's coming. We're not seeing past that game at the moment. In the back of your mind you do need to prepare for a short turnaround to play Japan, but we won't be taking this first challenge lightly. It's one we relish."

Saturday marks their 114th day in camp since the summer. A veritable eternity with the most pressurised day of all, still more than a week away. Success rides on staying focused amid this rugby marathon.