The Australian international will fly out after Sunday's Clydesdale Bank Premier League clash with Gretna to join his team-mates for a group qualifier against China in Kunming on March 26.

In addition to two long flights, the 24-year-old will have to prepare for a game at altitude before he returns to play against Rangers at Ibrox in a crucial SPL game three days later.

He said: "These are the sacrifices you have to make for your country.

"It's important for me because it's a chance to play in the World Cup. To turn my back on that would be pretty stupid.

"The gaffer has fully backed us as well. He's been great with everyone, he always wants his players to play for their country.

"We're playing somewhere near Tibet but I don't know too much about where I'm going.

"The game's being played above sea level to give the Chinese every chance of beating us.

"With the time difference the kick-off will be Wednesday morning here."

Despite the difficulties, McDonald is confident he will be in peak condition to face Rangers.

"Australia have physios and doctors in a set-up which is second to none," he said.

"We have doctors travelling with us on planes making sure we're sleeping at the right times, even giving us asthma pumps because we're playing above sea level.

"I had a lung test before I went away the last time.

"They said for me to cope in these conditions I'd have to take one of the asthma pumps.

"They'll be making sure we're well looked after and we come back in good condition because the last thing they want is clubs complaining about it and not letting us go the next time.

"I'll be back in Glasgow on Thursday.

"Last time I came back from Australia having played on the Wednesday we played Aberdeen on the Sunday and we won 5-1 and I scored a double.

"So it's okay as long as you look after yourself."