TIANJIN, China (AFP) - China's coach Vladimir Petrovic defended wholesale lineup changes ahead of their 1-0 loss to Qatar that all but saw his team's hopes of qualifying for World Cup 2010 in South Africa dashed.

A Sebastian Soria penalty in the 14th minute of Saturday's game was enough to earn Qatar the vital victory, putting them at the top of Group 1 with seven points alongside Australia, who hours later lost to Iraq 1-0.

Petrovic, from Serbia, took a beating in China's football-mad press Sunday for benching Manchester City midfielder Sun Jihai, experienced striker Han Peng and midfielder Du Zhenyu.

"We made the adjustments based on how we played in the first (June 2) match in Doha against Qatar, we thought the older players needed rest," Petrovic said in his post-match interview.

Five changes in the starting line-up included four players under 23 who will represent China in August's Beijing Olympics.

"We must allow some of the young players to play, they are the future and the hope of Team China," Petrovic said, apparently confirming that the team has given up its World Cup hopes for a stronger showing at the Olympics.

A dejected Petrovic offered to step down if his tactics were seen as ineffective.

China, at the bottom of the table with three points, must next Saturday beat reigning Asian Cup champions Iraq, currently with four points, and Australia later this month to keep their World Cup chances alive.

Meanwhile a red card to Sun for cursing the referee from the bench and a second yellow card to China's top defender Li Weifeng also in Saturday's match means that both stars will be unavailable for the Iraq game.

"It is very difficult for me to say why China's coach made the decisions he made, I'm sure he had his reasons," Qatar's Uruguayan coach Jorge Fossati told journalists.

"But the changes did not confuse me at all because the system China used was the same against us as in Doha, only this time the players were different."

Following the loss, China's players and coaches bitterly complained about the Lebanese referee Talaat Najm who awarded the visitors a questionable penalty kick while also meting out five yellow cards to the hosts.