James Holland slid into his club teammate Covic and a loud crack was heard when the two collided during the 11 v 11 session

Covic immediately left the pitch unaided and did not return. Socceroo officials were tight-lipped on the condition of the big Jets keeper.

If Covic is ruled out, it's likely Mark Schwarzer will be confirmed as playing and is likely to fly in immediately after his club game in Europe on the weekend. Sydney FC's Clint Bolton would be the obvious call up.

Meanwhile, and despite flying in from Norway in an economy seat this morning, Michael Thwaite looked remarkably fresh and trained well.

When asked about the effect of jet lag on the Socceroos flying in next week, Thwaite noted it is an issue but was not too concerned. “To be fair, the first 20 minutes is okay but after that in a game situation I think it's more of a mental thing.

"But these players are full on professionals playing in the biggest leagues in the world so I'm sure it won't be a problem.

“But once again, the head coach might select an A-League player who are just as good as the European players.”

Thwaite, who has signed with SK Brann in Norway in the last few days, was played as a right back at training and is hopeful his early arrival will boost his and fellow early arrival Jacob Burns' chances of playing against Qatar.

“Because he [Verbeek] doesn't know us, coming in early gives us a chance to show ourselves and he really wants to see us put under pressure at training.”

If Thwaite does play, he and the Socceroos will be roared on by a full house with officials today confirming only 4,000 tickets are left for next Wednesday's match against Qatar at Telstra Dome.

Meanwhile, Thwaite's new Norwegian club have drawn Tim Cahill's Everton in the UEFA Cup. “I've never played against a Premiership team before, so it should be very interesting,” added the Queensland born defender.