Anything other than an Iran win is unthinkable but the triple-champions may need a big victory against the abject co-hosts, who have already shipped 10 goals in two matches.

Finishing first is seen as vital with the top team staying here for the quarter and semifinals, while the runner-up faces trips to Indonesia, Vietnam and back to Indonesia and a potential last-four clash with Japan or Australia.

"Our first priority is to stay in Malaysia, no matter who our opponents are in the quarterfinals," said Iran coach Amir Ghalenoei.

With the top three separated only by a point, China can still win and top the group but defeat would mean an early exit and probably the sack for coach Zhu Guanghu.

China impressed in their 5-1 rout of Malaysia but squandered a two-goal lead in the 2-2 draw with Iran. Uzbekistan, ranked nearly 30 spots higher, also beat the home team 5-0.

China will also be hampered by the loss of suspended captain Zheng Zhi and defender Li Weifeng, while Zheng Bin, Zhou Haibin and goalkeeper Li Leilei will take late fitness tests.

"The absence of Zheng Zhi and Li Weifeng will definitely affect our team," admitted Energie Cottbus midfielder Shao Jiayi.

"They've been very important for us in the last two matches, especially Zheng Zhi. But we've been improving match by match and I'm sure we'll get a good result on Wednesday."

Uzbekistan coach Rauf Inileyev predicted China would shrug off the loss of Zheng and Li and promised a very different performance to their 3-1 friendly defeat in March.

"Losing those two players is not a big problem for China -- they have players who can play instead of them," said Inileyev, who has Islom Inomov out through suspension but should welcome back injured midfielder Aziz Haydarov.

"We're not thinking about revenge for March -- we just want to win the match and qualify. It will be different on Wednesday and you'll see the difference between the Asian Cup and a friendly."

Meanwhile, Malaysia are aiming only at damage-control with media baying for more changes after the heavy defeats prompted the football association's deputy president and two independent council members to step down.

"With all the criticism and all the humiliation I don't think the best psychologists could help the team now," the coach said.

"We have to be realistic -- we can't win against Iran but we have to make sure that they don't score too many goals."

Iran are seeking their first Asian Cup title in 31 years, while Malaysia are playing their first tournament since 1980 by virtue of co-hosting the event.

Uzbekistan reached the quarterfinals in 2004, when China reached the final on home soil. But China have been on a poor run and coach Zhu is under orders to reach the last four "or else."