The Blackburn Rovers striker suffered a recurrence of an Achilles tendon injury during training at Kilmarnock yesterday. Gallacher is rated as doubtful and will have a fitness test this morning.
The Scotland manager, Craig Brown, admitted that Gallacher's absence would seriously affect his plans to come up with the victory the nation is demanding. Gallacher has scored five goals in the last four qualifiers, including two against Belarus last month at Aberdeen.
"It would be a big blow to lose someone like Kevin but we will have another look at him tomorrow," Brown said. "He has scored against Austria, Sweden and Belarus in the group and is on fire for us. We have been seeking the right partner for him. Now we may have to look for two strikers."
Scotland overcame Latvia 2-0 in Riga last October - but Brown detects signs of progress in the former Soviet republic. "Their team is mainly made up of players from Skonto Riga and they are improving at club level," he said. "Skonto lost to Barcelona in the European Cup this season but gave them a real fright at the Nou Camp.
"After that experience I don't expect the Latvians to freeze in front of 50,000 at Parkhead. I am sure they will play a different way to Belarus. I expect them to try and take the game to us, not sit back."
The Latvians flew into Edinburgh yesterday and had their first training session at the Glasgow junior club, Maryhill, last night.Reuse content