The left-back captained Scotland as they travelled to face Spain in Seville, knowing a point would have been enough for them to seal their place at Euro 2024 next summer.
It was a frustrating night in more than one way though for Robertson, as he was forced off before half-time and his side then went on to fall to a 2-0 defeat.
Robertson had his arm in a makeshift sling as he was replaced, having stayed down in pain after Spanish goalkeeper Unai Simon landed awkwardly on him.
Scotland take on France in a friendly on Tuesday night, but boss Steve Clarke has confirmed that Robertson will play no part in that and will instead return to his club to be assessed.
“Andy has hurt his shoulder,” Clarke said after the match in Spain. “He will go back to his club now.”
Robertson has played every minute of Liverpool’s first eight Premier League matches of the season, but is now a major doubt for the Merseyside derby after the international break.
Liverpool host Everton on October 21 at the start of a busy run of matches, with back-to-back Europa League matches against Toulouse and a Carabao Cup clash away to Bournemouth in between their League fixtures.
