Macala's side lie third in Asian Group One, above fourth-placed Qatar on goal difference, having picked up four points from their first four games.

Second-spotted Japan are four points better off, two points behind Australia.

With the Socceroos not in action tomorrow, victory over Bahrain would see Japan move to the summit and strengthen their grip on a top-two berth which would secure automatic qualification to the showpiece event next year.

A Japan win would also leave Bahrain battling with Qatar and Uzbekistan for third place and a play-off berth for the right to face New Zealand for a trip to the World Cup finals.

"I know the situation we are in," assessed Macala. "In our small group, Japan and Australia are in the first group and Uzbekistan, Qatar and Bahrain are in the second group.

"It's a very important time as it will decide which group we are in."

Midfielder Abdulla Omar (not match fit) misses out tomorrow while Ala'a Hubail and defender Husain Ali are rested after hectic club schedules of late.

Japan coach Takeshi Okada expects Bahrain to be highly motivated as they look to keep alive their hopes of qualifying.

"It's going to be a tough game," he said. "If Bahrain lose, their chances of qualifying will be diminished.

"We'll attack with everyone and everyone will defend in order to show what we've been working on and make our home fans happy.

"We are not going to play for a draw and will make every effort to earn three points. We should take risks, but should also be careful not to be reckless."

The other game in Group One tomorrow is the Tashkent encounter between bottom-placed Uzbekistan and Qatar.

The hosts have managed only one point from their first four games and, despite Qatar being only three points better off, visiting coach Bruno Metsu claims tomorrow's match will not determine their fate.

"Despite its importance, the match against Uzbekistan is not decisive as we have a match against Bahrain four days later," said the Frenchman.

"However, if we want to qualify for the World Cup, we must go into our matches with a winning mentality.

"Our position is better than Uzbekistan. If we lose, we will continue to struggle, but if Uzbekistan lose they will lose every chance of qualifying."

Metsu will be without suspended defender Ibrahim Al Maged and injured duo Abdulla Koni and Mostafa Abdulla tomorrow.

Uzbekistan coach Mirdjalal Kasimov is missing centre-back Anzur Ismailov through suspension and Islom Inomov and Ildar Magdeev due to injury.

"We have to decide who will replace Ismailov," said Kasimov. "We also are without Islom Inomov and Ildar Magdeev due to injury.

"Ilyas Zejtullaev has just returned to the national team after a long break but is not fully fit.

"Nevertheless, we are ready for the match. We have no place to go and we will accept only a victory."