Injury-hit Japan face an immediate test of their World Cup credentials against North Korea Friday as Asia's top teams join the long road to the 2014 tournament in Brazil.
Australia host Thailand and South Korea are home to Lebanon as the region's highest-ranked sides enter the qualifying at the third round, with the process due to wrap up next year.
Iraq, the 2007 Asian Cup winners, play Jordan and China welcome Singapore as the group stage gets under way featuring five pools of four teams.
Asian champions Japan have been troubled by injuries to influential playmaker Keisuke Honda and recalled midfielder Kengo Nakamura as they prepare to face North Korea in Saitama.
Coach Alberto Zaccheroni described the losses as a "huge blow" but he had high hopes for 20-year-old Urawa Red Diamonds striker Genki Haraguchi, who looks set to make his full international debut.
"Haraguchi is good at both defence and offence, especially good at attacking from the left side to the centre. He has speed with skills. I think he is ready to play for the top national team," Zaccheroni said.
Japan, Asia's top-ranked team at 15, will face a North Korea side who have already voiced anger at their lowly FIFA placing of just 115, which has pitched them into a tough Group C also including Uzbekistan and Tajikistan.
Striker Jong Tae-Se, known as the "People's Rooney", said the rankings disadvantaged the isolated communist state, which proved its quality by reaching last year's World Cup finals in South Africa.
North Korea also had a cruel draw at the Asian Cup in January, when they bowed out at the group stage after being pitted against title-holders Iraq, three-time champions Iran and the United Arab Emirates.
"Isn't it strange that we always end up 100 percent in a group of death in any (major) tournament?" Jong wrote on his blog.
"I personally believe on my own that the biggest reason (for the low ranking) is that we as a socialist country cannot pay money to organise warm-up matches on international 'A' match days."
New-look Australia hope to start with a bang against Thailand as coach Holger Osieck looks to build on a successful year of just one defeat in 11, including wins against Germany and Wales.
The Socceroos, featuring a number of younger players alongside stalwarts such as Brett Emerton and Mark Schwarzer, will expect to shrug off the loss of injured attacker Harry Kewell when they face Thailand in Brisbane.
"I think our depth is fantastic after seeing players like (Michael) Zullo, James Troisi or (Adam) Sarota come through," Everton midfielder Tim Cahill said.
"It's fantastic to be a part of the last era and move forward to this era with these players. The transition is perfect."
South Korea will have pencilled in three points at home to Lebanon, while China will be hoping to impress their new boss, ex-Spain and Real Madrid boss Jose Antonio Camacho, against Singapore.
Ten teams -- winners and runners-up of the five groups -- will be drawn into two pools for the round-robin fourth stage, with the eventual top two in each section earning a ticket to Brazil.
The two third-placed teams will then face each other for the right to contest an intercontinental play-off.
Tajikistan were promoted to Group C after FIFA disqualified Syria for fielding an ineligible player in George Mourad, a midfielder who once represented Sweden.