Bolton Wanderers winger Gregg Wylde and Motherwell defender Steven Saunders have dropped out of the Scotland Under-21 squad to face Bulgaria.
But the Scottish Football Association has stressed that both players were aware of the likelihood before joining manager Billy Stark's training camp.
Wylde has not played since February because of registration problems after being released by Rangers.
Wylde joined Bolton after leaving Rangers but has not been allowed to play
Saunders has played once since picking up an injury in August.
But Stark, who always planned to trim his squad, wanted to assess both players after their periods of inaction and ensure that they continued to feel part of the Scotland set-up.
Dundee United striker Johnny Russell is currently with the senior Scotland squad preparing for Saturday's friendly against the United States on Saturday.
But he is with Craig Levein's squad purely for experience, is unlikely to play in Jacksonville and will join the under-21 squad on his return.
Fellow forwards Jordan Rhodes and Michael O'Halloran will both join up with Stark's squad after Saturday's play-off at Wembley as their respective sides attempt to win promotion to the Championship in England.
O'Halloran is on loan at Sheffield United from Bolton and will be in opposition to Rhodes' Huddersfield.
Tottenham Hotspur goalkeeper Jordan Archer will join the Scotland Under-21 squad after taking part in the Den Haag Youth Tournament this weekend.
Scotland are in Group A alongside Den Haag, Manchester City and Cruzeiro, with the other group consisting of Club Brugge, Borussia Monchengladbach and the national teams of Mexico and Kazakhstan.
Stark's under-21 side lie second, a point behind the Netherlands, ahead of their European Championship Group 10 qualifier against Bulgaria at Lovech Stadion on 31 May.
Scotland Under-21 squad
: G Adam (Rangers, on loan at Airdrie United), J Archer (Tottenham Hotspur), M Ridgers (Hearts)
: P Hanlon (Hibernian), R Jack (Aberdeen), R Perry (Rangers), G Shinnie (Inverness Caledonian Thistle), L Toshney (Celtic, on loan at Kilmarnock), D Wilson (Liverpool, on loan at Blackpool)
: S Allan (West Brom), S Armstrong (Dundee United), T Cairney (Hull City), L Kelly (Kilmarnock), K McLean (St Mirren), L Palmer (Sheffield Wednesday), D Wotherspoon (Hibernian), G Mackay-Steven (Dundee United)
: M O'Halloran (Bolton Wanderers, on loan at Sheffield United), J Rhodes (Huddersfield Town), J Russell (Dundee United).