Marcello Lippi's Guangzhou Evergrande face the only unbeaten team left in the tournament when they take on Japan's Kashiwa Reysol in the AFC Champions League semi-final first leg Wednesday.

The Chinese double-winners and hot favourites have swept into the last four for the first time, but they are now confronted by their toughest task in the form of Kashiwa.

While Kashiwa are just mid-table in this year's J-League, they have saved their best for the Asian competition -- helped by their Brazilian marksman, ex-Guangzhou striker Cleo.

The 28-year-old was deemed surplus to requirements by World Cup-winning coach Lippi, but after joining Kashiwa on loan he has become a regular starter, netting a couple of key goals in their run to the semis.

"I think we've had good results this year because the experience of playing in this competition last year has helped a lot," said Cleo.

"The high point so far was the quarter-final because we fought hard against Al Shabab in Saudi Arabia," he added.

"Coming through that game means we're the first Japanese club since 2009 to reach the semi-final. We're giving everything to achieve these excellent results."

Guangzhou, gunning to become China's first continental champions since Liaoning in 1990, have recent knowledge of the Japanese club after playing them home and away in last year's group stage.

The two teams shared a goalless draw in Japan before Guangzhou -- then featuring Cleo -- won the return match in China 3-1.

All four remaining teams are debutants in the Champions League semi-finals, but the two sides contesting Wednesday's other tie have history.

Iranian champions Esteghlal met South Korea's Anyang Cheetahs, now morphed into FC Seoul, 11 years ago in the semi-finals of the Champions League's precursor, the Asian Club Championship.

On that occasion, the South Korean team ousted Esteghlal by beating them 2-1 at Tehran's famous Azadi Stadium.

Since then, FC Seoul have twice suffered quarter-final exits in the AFC Champions League but they finally reached the last four by beating last year's runners-up, Al Ahli of Saudi Arabia, 2-1 on aggregate.

Like Seoul, Esteghlal have lost only once in this year's tournament and they are travelling to South Korea in confident mood after winning their last four away games in the tournament.