The nations that faced each other last week meet again on Saturday when 20 teams from five groups vye to advance. The top two teams from each group progresses to the last stage.

Asian champion Iraq has one point from its first three matches in Group One and needs nothing less than a win against Australia at its neutral "home" of Dubai.

The Socceroos won 1-0 in their recent encounter at Brisbane last Sunday to move onto seven points and a win away from booking their berth in the final round with two games to spare if second-placed Qatar defeats third-placed China at Tianjin.

As well as a desperate Iraq, Australia will have to contend temperatures that are expected to reach 41 Celsius (105 Fahrenheit).

"I hope they are broken mentally, but I don’t think so," Australia midfielder Mark Bresciano said. "Dubai is their last chance. We have work to do and it’s going to be very tough, especially in the conditions."

In Group Two, a win for Bahrain at home to Thailand will give the tiny Gulf nation a fourth successive win and a place in the final round of Asian qualifying for the second successive time.

Japan is three points behind the leaders after a 3-0 home win against Oman .

"I actually thought it would be a lot closer, a game decided by one goal," Japan and Glasgow Celtic playmaker Shunsuke Nakamura said.

The win eased some of the pressure on coach Takeshi Okada but cost Oman’s Uruguayan coach Juan Ribas his job. Hamad Al Azzani has taken the position on a temporary basis ahead of Oman’s must-win game against Japan in Muscat.

South Korea, which let a two-goal lead slip at home to Jordan last weekend, remains on top of Group Three, but only just. A defeat in Amman on Saturday will put the 2002 World Cup semifinalist hopes of a seventh successive World Cup appearance in grave danger.

"We have talked about and thought about last week’s performance." said Korea coach Huh Jung-moo after a 17-hour journey to the Jordanian capital. "The players know that it is important to bounce back in this match."

North Korea has scored just one goal in three games, but its defense has yet to be breached, though Turkmenistan missed a penalty last weekend. A win at home in Pyongyang will put the 1966 World Cup quarterfinalists in sight of a second straight final-round continental appearance.

Uzbekistan has been the star of Group Four with three wins. A stunning 7-3 victory over Singapore at the Singapore National Stadium was the latest in a series of impressive results.

"It all came together," Uzbek coach Rauf Inileev said. "We are playing well at the moment, but there is still much hard work to do."

Singapore travels to Tashkent for the return leg in the knowledge that another defeat will almost certainly end its chances and send the Central Asians on.

Saudi Arabia is three points clear of Singapore and another win over pointless Lebanon will tighten its grip on second place.

Asian powerhouse Iran has yet to win in Group Five. After three draws, Iran sits two points behind group leader United Arab Emirates and Syria in second.

Syria defeated Kuwait in 1-0 in game three causing the losers to fire Croatian coach Rodion Gacanin

With a tough game at the UAE to come, Iran is without injured players Ali Karimi, formerly of Bayern Munich, and Mehdi Mahdavikia of Eintracht Frankfurt.

Defeat in Al Ain would leave Iran’s hopes of a fourth World Cup hanging by a thread, but coach Ali Daei is confident that won’t happen.

"I believe Iran can defeat UAE because the team played well against them in Tehran and deserved to win," he said.