ADELAIDE United must beat China's Jiangsu Suning in the final Group H match of the AFC Champions League at Hindmarsh on May 9 and it must rely on Gamba Osaka upsetting Jeju United to stay alive for the knockout stage of the tournament.
After Adelaide staged a remarkable comeback from a 2-0 deficit to draw 3-3 with Gamba at the Suita City Stadium on Tuesday, Jeju United defeated table-topping Jiangsu in the later match 2-1 in China to move two points clear of the Reds.
With Jeju now on seven points and in second place and Adelaide in third spot with five points United must win at Hindmarsh and hope Gamba beats Jeju in South Korea also on May 9 to ensure a clear pathway in joining Jiangsu (12 points) to the second stage of the tournament.
If the Reds win and Jeju is held to a draw with Gamba, both sides will be tied on eight points.
Adelaide will go through on the Asian Football Confederation's head-to-head rule after United drew 3-3 with the South Koreans at Hindmarsh before beating Jeju United 3-1 away.
But a last gasp goal from Baba Diawara gave United a vital lifeline to making the knockout stage of the intercontinental tournament after Adelaide got off to a worst possible start, shipping two goals in the opening 12 minutes.
Evergreen Gamba skipper Yasuhito Endo engineered the first goal when his inch-perfect corner saw big Shun Nagasawa lose his markers before beating captain Eugene Galekovic at the near post with a clinical header to give the hosts a 1-0 lead in the sixth minute.
Just seconds earlier Hiroki Fujihara had Galekovic palming the ball away for a corner after Gamba broke Adelaide's lines with neat triangular passes.
Teenager Rutsi Doan made it 2-0 six minutes later when he received the ball from Yusuke Ideguchi outside the box.
He cut inside looked up saw Galekovic was positioning himself for a cross before blasting a perfect 22m shot into the back of the net which caught the Reds keeper off guard.
But Adelaide clawed its way back after North Korean Jun-Ya Kim slipped with Baba on his tail.
The Senegalese striker dribbled the loose ball towards the box to see Sergio Cirio making a great run which lost two Gamba defenders.
Baba cut the ball back to Cirio who made no mistake to peg back the deficit two minutes before the break.
Jordan O'Doherty then levelled the score with a 25m rocket into the top corner after Isaias and Baba combined to set up the 19-year-old's first goal in the tournament in the 54th minute.
Three minutes later Adelaide was let off the hook when Endo sent a penalty kick into the stands after Ben Garuccio gave away the spot kick when he fouled Jae-Suk Oh inside the box.
Adelaide was then dealt a cruel blow when Michael Marrone unfortunately turned the ball into his own net with Nagasawa honing in on a Gamba cross.
Gamba's third goal incensed Isaias who thought Baba was fouled on the halfway line before the Japanese moved forward in transition to score.
But Baba proved Adelaide won't lie down for anyone forcing an equaliser with a brilliant headed finish in stoppage time after a Garuccio set-piece stunned the home side.
Adelaide fielded a makeshift line up for the suspended trio Taylor Regan, Dylan McGowan and Riley McGree.
Mark Ochieng earned a start at right back and Ben Warland made his Champions League run-on debut at centre back, partnering Marrone while O'Doherty earned a midfield berth.
O'Doherty had a bright start replacing McGree but the teenager will now miss Adelaide's final match against Jiangsu when he picked up his second booking of the campaign meaning he will be suspended for the clash against the Chinese super club.
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