It would be a major shock. Big-spending Guangzhou, led by Italy's 2006 World Cup winning coach Marcello Lippi, is expected to become the first Chinese team to win the tournament. The Italian coach, appointed in May 2012, also wants to become the first coach to win both Europe's Champions League and its Asian counterpart.
With the team full of Chinese internationals as well as Dario Conca from Argentina and Elkesen of Brazil, who scored two goals each in the first leg, Guangzhou needs to win just one of its remaining five games in the Chinese Super League to clinch a third successive domestic title.
"I don't think we have got (a place in the final) yet," said Lippi. "I'm 64 years old this year and have been in the coaching business for 30 years, and from that experience I can tell that you that you never know what will happen next in football, and Reysol have ability and were a tough side to play this time."
Esteghlal of Tehran is not only flying the flag for Iran but for the whole of the west Asian region. The two-time continental champion lost 2-0 at Seoul in the first leg.
The situation is retrievable at the 90,000 capacity Azadi Stadium in Tehran but Esteghlal will be without star international midfielders Javad Nekounam and Andranik Teymourian, who are suspended after picking up yellow cards in Korea.
"In Tehran we can score two goals," said coach Amir Ghalenoei, who took Iran's national team to the 2007 Asian Cup. "We will attack a lot and we will play to the best of our abilities in the second match."
Seoul is on an unbeaten run of 12 games domestically. Six K-League teams have been crowned champions of Asia but Seoul had never progressed past the quarterfinals before this season.
Inspired by the goals of Montenegro international striker Dejan Damjanovic and driven on by South Korea internationals Ha Dae-sung and Yun Il-rok, Seoul is not taking anything for granted.
Coach Choi Yong-soo has reminded his players of the 2004 AFC Champions League final when Seongnam Ilhwa Chunma, just to the south of the Korea capital, won the first leg 3-1 away at the home of Saudi Arabia's Al Ittihad only to lose 5-0 at home in the second leg.
The Korean team will also have to handle the tough environment of Tehran as well as an altitude of over 1000 meters.
"The altitude will have an effect with the ball bouncing differently and with the shooting speed," said Choi. "This is something that we have to think about and prepare for but we will do our best and it will be a good experience for our players."
