The Japanese side is hosting the opening clash against Hernan Crespo’s team from the UAE at Yokohama International Stadium and aims to become the seventh different club from the country to win the continental crown.
Marinos have been Japanese champions on five occasions but have never won the Asian title.
Kewell wants his players to adopt a level-headed approach to the opening game as they seek their maiden title.
“You’re going to have to be able to control your emotions,” the former Australia international told the Asian Football Confederation’s official website.
“You’re not going to be out of it from the first game. You’re always going to have a second chance.
“This is something that myself, my team, the fans and the club are all going to have to appreciate and understand.
“Whatever happens on May 11 is not going to determine everything. It’s going to put a marker down for the following game, so it’s something I’m not used to but I’m going to have to get used to it quickly.”
Marinos have not reached the final of Asia’s premier club competition since losing the 1990 decider when they were known as Nissan FC.
They have endured a rollercoaster journey, with Brazilian striker Anderson Lopes scoring in the last minute of extra-time to eliminate Bangkok United in the last 16.
They then saw off China’s Shandong Taishan in the quarterfinals when down to 10 men.
Marinos also had a man sent off in the dramatic second leg of their semifinal against Ulsan Hyundai, with the J.League side downing the South Koreans in a penalty shootout.
“We’ve had to endure some difficult moments to qualify but I feel, the way we want to play the game, sometimes things can happen,” said former Liverpool winger Kewell.
“I’m a firm believer in being able to adapt, and I think in the lead-up games to the final we’ve had to adapt.
“We’ve always had a man sent off, which is not fantastic, but we’ve been able to deal with what comes next.
“That shows me that this team is prepared and able to sacrifice the style of play to back it up with hard work.”