Magnus Bradbury has been backed to fill Hamish Watson's shoes for Scotland – but there could be further injury woe for Gregor Townsend as the Dark Blues sweat on Ali Price.
Townsend's team have suffered a nightmare start to the World Cup, with the news that Edinburgh flanker Watson has been ruled out of the tournament coming less than 24 hours after the dismal loss to Ireland in their Pool A opener.
And there could be further anguish ahead after Price was spotted on crutches as his team boarded a bullet train from Tokyo to their next base in Kobe.
Assistant coach Danny Wilson says it is too early to tell how serious the Glasgow scrum-half's ankle knock is but it would complete a miserable 48 hours if Greig Laidlaw's understudy is told he needs to follow Watson onto an early flight home.
"He is going through the assessment," said Wilson. "We got back to the hotel late last night and then we've been travelling to Kobe, but over that time the assessment process has been sorted so we should by the end of play have a bit more information.
"At the moment, a minor issue around the foot and ankle area, but we'll have to wait and see when the full assessment has been done."
Forward Watson was taken off by stretcher after suffering a serious knee injury during the shocking 27-3 defeat in Yokohama after he was caught in the midst of a painful ruck tangle with Cian Healy and Tadhg Furlong.
A scan confirmed his worst fears and the 27-year-old will play no further part.
His Edinburgh club-mate Bradbury, who had already travelled to Japan on stand-by as a precautionary measure after fellow back-rower Jamie Ritchie suffered a facial injury, will now join Townsend's team officially as they gear up for their crucial clash with Samoa next Monday.
And the head coach said in a statement: "While there is a high probability of picking up injuries during a World Cup, it's always disappointing to see someone having to head home.
"We feel for Hamish who had worked so hard for this opportunity and wish him well in his recovery."
But forwards specialist Wilson believes Bradbury can give Scotland a new dimension.
"It is obviously a major blow, losing Hamish from the squad," he said, "But I'm pretty confident that Magnus can come in and bring a ball-carrying presence that we maybe didn't have, and we showed we didn't have last night.
"So there is an addition and a strength that has been added there."
The Dark Blues were meek in the face of the tigerish men in green and three mistakes allowed Joe Schmidt's men to kill the game off with three tries inside the first 25 minutes.
Scotland now face three do-or-die clashes with Samoa, Russia and then Japan as they look to rescue their hopes of making the last eight.
But Wilson shrugged off the suggestion it is time to lower the expectations placed on Townsend's men.
"There is only one thing you can do now, we move on to three games that are must-win games now," he said. "If we had won last night we would probably be saying we need to win the next three games.
"We now have to make sure we improve the performance against Samoa, and against the other two opposition, to give ourselves the opportunity to qualify. They become games now that we have to win, it is as simple as that.
"Scotland is a very proud nation in terms of its rugby history. I'm fully aware of that walking into the job. We need to rise to that challenge. We certainly have a consistency issue, I think that would be fair to say.
"You've seen some outstanding performances, some outstanding rugby played, some great tries and some big wins.
"You've also seen the other side of that.
"We as a coaching team need to find a way of consistently producing the kind of quality rugby we need to produce to win games, and if we're being brutally honest about it we've got to eradicate some of the errors we make and the pressure we heap on ourselves."