Top spot, and the one guaranteed place at Korea/Japan 2002, in Group A of Asia's World Cup qualifying tournament has come down to the last round of matches as leaders Iran face up to Bahrain and second-placed Saudi Arabia meet Thailand in a nail-biting finish to the stage.

FIFA's decision to delay the kick off of both matches until Sunday has only heightened the tension as the Middle East's biggest rivals go into one of the most important weekends in the history of the game in each nation.

Iran are in the driving seat, with a win against Bahrain in Manama enough to take them to their second consecutive World Cup finals no matter what happens in Riyadh.

With a one-point lead at the top of the group, Miroslav Blazevic's side have their destiny in their own hands, earned thanks to their late draw against the Saudis in Jeddah earlier in the month.

The clash between Iran and Saudi has turned into the most vital match of the qualifying tournament and the defensive error in the dying minutes that allowed Sirous DinMohammadi to hit the equaliser for the Persians could well be the moment Iran guaranteed their qualification for the finals on Korea and Japan next year.

Iran will go into their game against Bahrain without left wingback Mehrdad Minavand, one of the team's outstanding performers during the qualifying stages who picked up his second yellow card of the tournament in the 1-0 win over Thailand last weekend.

Goalscoring has been a problem for the Iranians and the pressure will be on Ali Daei to lead from the front and hit the goal that will take his team to the finals.

Bahrain, too, will be without several of their top names, with captain Faizal Abdul Aziz banned by the national association after leading a group of players on an overnight stay to the Thai city of Pattaya last weekend without receiving clearance from team officials.

Also out is striker Yousef Amer Al Sadi, the hero of Bahrain's qualification for the this stage of the competition at the expense of Kuwait, another victim of the association's swift justice.

For the Saudis, coach Nasser Al Johar will be hoping his side can repeat their 3-1 win over the Thais in Bangkok in September to qualify for their third straight World Cup finals.

The Thais have yet to record a win in their first seven games but with four draws to their credit they are more than capable to upsetting the Saudis and helping Iran towards their goal of qualification.

With China sealing first place in Group B several weeks ago and Uzbekistan's surprise capitulation to Oman last week, the United Arab Emirates are favourites to take the runners-up spot when the final matches in that group kick off on Friday.

A draw against Oman will be enough while Uzbekistan have to hope they can defeat the Chinese in Tashkent and that Rashed Jaber's Oman side can repeat their performance last week in Muscat.

The runners-up in each group will meet for the right to play the Republic of Ireland in the play-off for Asia's final half-place at Korea/Japan 2002.