Hernan Crespo's Al Ain steamrollered 10-man Yokohama F-Marinos 5-1 in the Asian Champions League final return leg to lift the trophy for the second time in their history on Saturday.

The hosts trailed 2-1 from the away fixture but two goals from Soufiane Rahimi, a Kaku penalty and Kodjo Laba's late double ensured a 6-3 aggregate victory after Yokohama goalkeeper William Popp saw red just before half-time.

Al Ain, the oil-rich United Arab Emirates' most successful club, won the inaugural Champions League final in 2003 and were runners-up in 2005 and 2016.

"It's really difficult to describe the emotions," said Crespo, who only joined Al Ain in November and was mobbed by jubilant players as he spoke to reporters.

"We deserve this title. Every time we were facing the quarter-finals, semi-finals and even the finals as underdogs," he said.

"At the beginning nobody believed in us and we did it. These guys, these players did something big."

En route to the final, Al Ain ousted Cristiano Ronaldo's Al Nassr in the quarter-finals and ended the record, 34-match winning streak of Saudi giants Al Hilal in the semis.

However, Yokohama coach Harry Kewell was left fuming over the first-half penalty, criticising the referee and what he called a lack of sportsmanship by Al Ain.

"We play at a level where sportsmanship is supposed to be high. For me, the referee tonight was poor and he allowed certain things to happen. It was never a penalty," said the Australian.

"It's pretty hard to get a structure when you're playing against a referee that was terrible... it hurts, it really hurts," he added.

- Yokohama feel the heat -

Crespo had promised "hell" for Yokohama and thousands of fans in white robes and headdresses let off flares and chanted outside before packing out Hazza bin Zayed Stadium.

With temperatures still hovering above 30 degrees Celsius (97 degrees Fahrenheit) at the 8:00 pm kick-off, Al Ain were ahead after just nine minutes.

Yahia Nader's sweet backheel wrong-footed the defence and tournament top-scorer Rahimi rifled a low shot into the net for his 12th of the competition.

Ken Matsubara had a fizzing shot tipped wide but Al Ain doubled their advantage in the 34th minute after Shinnosuke Hatanaka brought down Rahimi in the box.

After a VAR review, Uzbek referee Ilgiz Tantashev pointed to the spot and Paraguay international Kaku smashed it into the bottom right, sparking delirium in the stands.

Al Ain's joy was doused as Yokohama's Yan Matheus stole a bouncing ball from Kouame Kouadio, then turned the defender inside-out and finished left-footed to make it 2-1 and 3-3 on aggregate.

But the half -- which stretched to an extraordinary 62 minutes -- finished badly for Yokohama when goalkeeper William Popp felled the on-rushing Rahimi and was sent off deep into injury time.

After the restart, a depleted Yokohama lived dangerously when Hatanaka, under pressure from Rahimi, parried a deep cross onto his own crossbar.

The visitors were creaking and on 67 minutes, Rahimi picked up a rebound, rounded a defender and lashed it past substitute 'keeper Fuma Shirasaka at his near post.

The goal knocked the stuffing out of Yokohama, who also had Hatanaka stretchered off, and Togolese substitute Laba pierced their porous defence twice in another long spell of injury time.

With their victory, Al Ain also reach the new-look, 32-team Club World Cup, which will be staged next year in the United States.