Bournemouth winger Ryan Fraser has become the latest player to withdraw from the Scotland squad for the end-of-season friendlies with Peru and Mexico.
Newcastle United midfielder Matt Ritchie and Wolverhampton Wanderers full-back Barry Douglas had already dropped out of Alex McLeish's travelling party earlier this week.
Hearts defender John Souttar is also facing a race against time to be fit enough for the trip, which sees the Scots face Peru in Lima on May 29 and Mexico in Mexico City on June 2.
McLeish named seven uncapped players for the Latin American friendlies which included Souttar, Celtic's Lewis Morgan and Hibernian left-back Lewis Stevenson.
The other four uncapped players are goalkeepers Jordan Archer of Millwall and Jon McLaughlin of Hearts, and midfielders Graeme Shinnie of Aberdeen and Hibernian's Dylan McGeouch.
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