Liverpool duo Xherdan Shaqiri and Andy Robertson are both set to miss Euro 2020 qualifiers.
Switzerland attacker Shaqiri will miss this month's games with Georgia and Denmark due to a groin injury, the Swiss FA has announced.
Robertson will miss Scotland's trip to Kazakhstan on Thursday due to a dental problem but will join up with the team in San Marino on Friday.
"The attacking midfielder is suffering from a painful inflammation in the groin," the Swiss FA said on its website.
The 27-year-old missed training on Monday and was instead examined in a Zurich hospital.
Switzerland coach Vladimir Petkovic will name a replacement on Tuesday for their opening Euro qualifiers away to Georgia on Saturday and at home to Denmark three days later.
The Liverpool player has not started a game for his club since the end of January, and has not featured for the side since a goalless draw against Man United in February.
He was an unused sub in Liverpool's 2-1 win over Fulham at the weekend and has scored six goals for the Premier League leaders so far this season.
Left-back Robertson missed the team flight to Astana with a dental problem which required surgery but there were suggestions he could make his own way and be ready for the match.
However, the Scottish Football Association confirmed he will be absent for the Group I opener but will be available for the match against San Marino three days later.
Scotland captain Robertson played in the Premier League win over Fulham on Sunday and is set to be replaced at left-back by Kieran Tierney.