Dundee manager Tony Docherty says his players are "in really buoyant mood" ahead of Saturday's visit to Celtic Park.
On-loan Forest Green Rovers forward Amadou Bakayoko was in action for Sierra Leone in their 2-1 defeat by Guinea-Bissau, Liverpool defender Owen Beck with Wales Under-21s, while midfielders Lyall Cameron and Josh Mulligan were with the young Scots.
"Bakayoko has just come back and he scored in his game, so he's came back feeling good about himself," Docherty told DeeTV.
"Owen Beck - they were victorious against Lithiania. He had a good game.
"And the two Scottish boys done well for Scotland Under-21s against Spain. Both played.
"So when they come into camp as buoyant as that along with the way the boys are just now, we're in good fettle. We've had three good training days."