Scotland midfielder Billy Gilmour has been ruled out of the World Cup after suffering a knee injury in the win over Curacao.
The 24-year-old fell to the turf with no one around him in the first half of at Hampden and was immediately substituted.
A scan after the game revealed Gilmour has damaged his knee and he will now return to his club side Napoli for rehabilitation.
Scotland's first World Cup game is against Haiti in Boston in a little over two weeks.
Scotland boss Steve Clarke said: "I am devastated for Billy because he has been an integral part of our World Cup qualifying campaign. The timing of this injury is so, so cruel and we all feel for him.
"He knows what we all think of him as a footballer and a person and while no words will give him any comfort tonight, I am certain Billy will have many major tournaments ahead of him in the future."
Gilmour's replacement has not yet been confirmed, but Clarke revealed in his post-match news conference that Udinese's Lennon Miller, Rangers' Connor Barron and Sparta Prague's Andy Irving are all on standby.
Manchester United youngster Tyler Fletcher, 19, is not in the World Cup squad but made his debut against Curacao as one of five young players who trained with the men's squad this week.
"Those three are on standby and obviously Tyler joined us this week," said Clarke.
"He's trained well this week, so he's a little bit closer than the other three, but I'd need to have a big discussion with my staff and decide the best way to go."
Fletcher is the son of former Scotland captain Darren Fletcher - who earned 80 caps during his 14-year international career.
Scotland struggled against Curacao in the early stages and found themselves 1-0 down after Tahith Chong's goal but a red card for Jurgen Locadia seven minutes before the interval swung the game back in Scotland's favour, even if Clarke would rather that both sides kept a full complement on the pitch.
"The red card obviously changes the whole dynamic of the game and from there, at least, against the 10 we managed to start creating chances and got a few goals," he said.
"It is obviously nice to win any international game, but I think it would have been better if it stayed 11 vs 11 and then we'd have been asked more questions about finding the spaces on the pitch - could we create the chances that we created against 10 men against 11? That would have been a better exercise for us."
