[USA-AUSTRALIA] As the clock ticks down to the start of the World Cup, injuries -- or the possibility of injuries -- are of primary concern.

U.S. forward Jozy Altidore was held out of field training Friday afternoon as he continues to recover from a mild sprain to his right ankle suffered in training two days earlier.

That means he's unlikely to play against Australia in their friendly on Saturday in Roodepoort (TV: ESPN2, Galavision, 8:30 a.m. ET).

The Socceroos, meanwhile, express concerns about the Ruimsig Stadium turf.

Australia will be training at Ruimsig Stadium before its opening game against Germany on June 12 and hope the turf, which has deteriorated over the past year, lasts.

"We are thinking, of course, about plan B and plan C," said Coach Pim Verbeek, "but let's see first tomorrow how it looks."

Verbeek is not going to take a chance on midfielder Brett Emerton, while Harry Kewell will be on the bench but may play.

"I am just taking no risk for [Emerton]," Verbeek said. "He is too important for us. We have three tough games in qualification, so I want him fit next week."

U.S. right back Steve Cherundolo knows what it's like to be injured so close to the start of the World Cup. A late addition to the World Cup 2002 team after Chris Armas and Greg Vanney were injured, Cherundolo was himself injured and couldn't play in the finals.

“I certainly don’t expect anybody to be playing in a reckless manner tomorrow," he said of the final tuneup, "but the best way to get injured is to go out and try not to get injured. Guys are going to go into tackles, and play hard, but I don’t think you’ll see any reckless tackles or any sort of dirty tackles that would be rewarded with a red card during a game."

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