Garry O'Connor serverd under Bobby Williamson at Hibernian

And, speaking on BBC Radio Scotland's Sportsound, Williamson expressed sympathy for the Lokomotiv striker.

"When I was the manager of Hibs, Garry would go away with the squad and he would end up back at Easter Road on the Monday or Tuesday," said Williamson.

"I would think 'What's wrong?' and he would say he had a migraine, or a stomach upset."

Former boss shows O'Connor sympathy

O'Connor failed to join up with the Scotland squad on Sunday as they prepared for Wednesday' s match in Ukraine and has now returned to Moscow.

"I wasn't terribly surprised," added Williamson. "And I wasn't surprised that he missed the previous (midweek) game and didn't go to Lithuania.

"But I think the boy is relatively shy when he's meeting new players. Even in the dressing room, he always kept himself to himself.

"Out in the training ground, he would joke around and play football, but I always felt that he found it difficult to mix with other players."

Recent reports suggest the 23-year-old could be homesick and keen for a return to the UK.

I might be making up excuses for him, but that's the view I got from him, that he didn't like being away in these get-togethers Bobby Williamson, former Hibernian manager

"When I first heard that Garry that was going to Russia, I thought it was too far away and it would be very difficult for him with a young family," added Williamson.

"When he started in Russia with his partner, they couldn't speak the language or go out to restaurants - or anywhere for that matter - and that's a big blow for him.

"But the biggest blow is that he can often be two days in camp before a game.

"If Lokomotiv Moscow have got two games a week, that's four days he's away from his girlfriend, and she's left on her own to deal with a little kid.

"I think he may be getting pressure from her as well. They're only a young couple."

Close family

Williamson added that O'Connor has always had strong support from his parents, and hopes this recent episode will not impact on the player's future career with Scotland.

"His mum and dad were always at Hibernian games, and I knew he would be missing them.

"I hope that's one of the reasons why he didn't go, that he just wanted to spend more time with his family.

"I might be making excuses for him, but that's the view I got from him - that he didn't like being away in these get-togethers, and I find that a shame because he's got a fantastic talent.

"There's two losers here: Scotland and Garry.

"I hope I'm wrong, I hope he knuckles down, gets on with it and gets all the help he needs to integrate himself with the Russians and play a big part for them, because he could become a better player for them and for Scotland.