Adelaide United coach Guillermo Amor says Gamba Osaka’s Asian Champions League experience may have been too much for his side in its 3-0 loss at Hindmarsh Stadium on Wednesday.

The Japanese giants were too good for Adelaide in their opening Group-H clash and Amor felt Gamba’s big stage familiarity was the difference.

The J.League side has competed in eight Asian Champions League campaigns since their first appearance in 2006 and won the tournament in 2008 when they defeated Adelaide United 5-0 on aggregate in the final.

The gap in experience was also highlighted with Reds midfielders, 18 year-old Riley McGree and 19 year-old Jordan O’Doherty facing off against Japanese football icon, 37 year-old Yasuhito Endo who has racked up over 500 J.League appearances and 150 caps for Japan.

“We speak yesterday (Tuesday) about they (are) always in Champions (League),” Amor said.

“The experience is very important in this competition.

“Big clubs control the games, control the situation, it’s very important.”

Amor applauded Gamba, who were ruthless in executing perfectly away from home.

The Japanese side made the most of their forays into the front third, punishing United with two first-half goals.

After the break, Amor noted Gamba’s change of tactics which forced United to attack if they held any hope of trying to salvage a result.

“The big teams normally have this,” he said. “They arrive the first time and it’s (a) goal, the last minute of the first half and it’s (a) goal.

“The second half with 0-2, (they were) in defence, they don’t want the ball and wait for the opportunity.

“And after it arrives 0-3. This is minimum effort, maximum performance and this is the big teams.” 

Adelaide coach Guillermo Amor says experience is very important in the ACL. Photo: AAP

Despite being outclassed and overpowered, Amor was pleased with Adelaide’s performance in patches, especially the period between Gamba’s first and second goal, where the Reds had two decent chances.

“We played well in moments,” he said.

Gamba coach Kenta Hasegawa anticipated a challenging fixture but felt the tide turn in his favour after the opening goal.

“I thought it was going to be a very difficult game today,” he said.

“But actually we broke the deadlock and scored a second one which was a good start.”