Japan booked their place at the London Olympics with a 2-0 win over Bahrain Wednesday, earning the country a shot at its third major title in a row.
Second-half goals from Takahiro Ogihara and Hiroshi Kiyotake were enough to put the 1968 bronze medallists through with already qualified South Korea and UAE, who won a five-goal thriller against Uzbekistan.
Syria, Oman and Uzbekistan will contest the Asian play-offs in Vietnam this month after finishing runners-up in the three groups.
Elsewhere Australia rounded off their failed campaign with a goalless home draw against Iraq, meaning Aurelio Vidmar's men played all six qualifiers -- some nine hours of football -- without scoring once.
South Korea, who had qualified with a game to spare as winners of Group A, stayed unbeaten heading into the London-based contest with a 0-0 draw against Qatar in Seoul.
Syria made certain of the play-offs with a 3-0 win over Malaysia. They were joined by Oman, who drew 1-1 with Saudi Arabia, and Uzbekistan, whose hopes of automatic qualification were dashed after a 3-2 defeat to UAE in Tashkent.
The hosts were two goals up at half-time, which would have been enough to supplant the Group B leaders, but an Ahmed Khalil double put UAE back in control before Saleh Haboosh hit the winner deep into injury time.
In Tokyo, Urawa Red Diamonds midfielder Genki Haraguchi crossed for Cerezo Osaka's Ogihara to open the scoring for Japan 10 minutes after the break.
And there was to be no way back for Bahrain, who had harboured faint hopes of reaching the play-offs, when Kiyotake netted four minutes later.
Japanese confidence will be high after their senior national team secured the Asian Cup early last year, followed by a historic World Cup title for the nation's women.
"I have a lot of players with potential. We qualified for the Olympics, but this is merely a start," said Japan's coach Takashi Sekizuka. "It was really tough to get through the Asian qualifying rounds. I feel relieved."
Iraq's draw in Gosford meant they finished ahead of Australia in third spot in Group B with five points, and the hosts were consigned to bottom place.
It is be the first time since 1984 that Australia will not be represented in football at the Olympics. Iraq finished fourth in Athens in 2004.
Football is played at under-23 level at the Olympics, although each team can pick up to three senior players.
Oman, Uzbekistan and Syria will contest the Asian play-offs in Vietnam from March 25-29, with the winner facing Senegal in England's Coventry on April 23.