By ESPNSTAR.com staff
Heading into the game at the Jar Stadium with the score locked at 2-2 on aggregate, the Reds edged ahead through Iain Fyfe after four minutes, only to see it cancelled out by Lutfulla Turaev in the 20th minute.
Three minutes after the hour mark, Jeronimo Neumann put Adelaide in front once again but 11 minutes later, Akmal Shorakhmedov equalised for Bunyodkor for the second time in the match, before the visitors were reduced to ten men at the end when Fabian Barbiero received his marching orders.
Bunyodkor themselves had a man sent off in the first half of extra-time when Anvar Gafurov picked up his second yellow, but the Uzbekistan outfit continued to press on and eventually sealed their progress thanks to a close-range header from Alibobo Rakhmatullaev six minutes from time.
And despite the 3-2 defeat meaning Adelaide were eliminated 5-4 on aggregate, Valkanis insisted he was proud of the fight his players displayed.
"In the second half, we had a red card which made it very hard and just like the first leg, we were about to make a change to become a little more attacking and try to win the game," he said on the AFC's official website. "But with the red card we had to change our plans.
"Playing with 10 men was very hard and you have to consider two games playing with a man less and travelling such a long way took its toll.
"But we are extremely proud of our players and they showed enormous character and fight until the end and even tried to poach a goal in the end."
Valkanis did admit that Bunyodkor had posed an extremely tough test to the Reds, especially after the hosts had gone behind early on.
"Bunyodkor were very good in the first half even though we opened the scoring," he added. "It seemed like after our first goal they picked up and went into third gear.
"We should have probably controlled the game a little more as we turned over the ball and put ourselves under a lot of pressure."
Adelaide kick off their Hyundai A-League campaign on Sunday when they travel to the Hunter Stadium to take on Newcastle Jets.