Sao Paulo, Brazil >> Forward Jozy Altidore, who left early in the United States’ opening match of the World Cup with a strained hamstring, should be available to face Belgium in the second round, coach Jurgen Klinsmann said Friday.

Altidore did some light jogging at training.

"We are very optimistic," Klinsmann said afterward. "Every day is a big step forward with Jozy. It’s 11 days now, and it’s looking better every day."

It is uncertain whether Altidore will be placed into the starting lineup Tuesday in Salvador, Brazil, given the length of his layoff.

But his presence would bring needed depth and would provide help for Clint Dempsey in what is expected to be a fierce game against a high-powered Belgian attack and a defense that surrendered only a penalty-kick goal in three group matches.

Midfielder Jermaine Jones broke his nose during Thursday’s 1-0 loss to Germany but is expected to play against Belgium without a protective mask.

Vincent Kompany, Belgium’s captain and sturdy central defender, did not practice, and his availability against the Americans is uncertain.

He sat out Thursday’s final group match against South Korea with a groin injury. A team spokesman said that Kompany had a "50-50" chance of playing Tuesday.

"We will do everything in our power to make sure he comes back 100 percent," coach Marc Wilmots said at the team’s training camp in Mogi das Cruzes, Brazil, outside Sao Paulo.

But Wilmots said it was "impossible to say now" if Kompany would be available.

Thomas Vermaelen, who could replace Kompany, did some light training while recovering from a hamstring strain.

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