Last year's AFC Champions League semi-finalists Bunyodkor made a strong start to the 2013 edition of the tournament on Wednesday.
The Uzbekistani powerhouse stunned reigning J.League champions Sanfrecce Hiroshima with a 2-0 away win in Group G.
Bunyodkor had not played a competitive game since November but they started well and took the lead on the stroke of half-time through Oleksandr Pishchur.
And they wrapped up the three points when Fozil Musayev added a second four minutes from time.
The other match in the group saw South Korean side Pohang Steelers draw 0-0 at home to Beijing Guoan of China.
Striker Cleo scored the only goal as Kashiwa Reysol claimed a 1-0 win at Guizhou Renhe in Group H.
The Brazilian headed home just before half-time to give the Japanese club an ideal start to the competition.
The group's other game saw A-League club Central Coast Mariners held to a scoreless draw by Suwon Bluewings.
Nick Montgomery missed an 88th-minute penalty for the hosts, who dominated the South Koreans for much of the encounter but were made to rue a wasteful display in front of goal.
There was no shortage of goals in Group D where United Arab Emirates outfit Al Ain came from behind to claim a 3-1 home win over Al Hilal of Saudi Arabia.
Abdullah Al Zoari had put the visitors ahead after nine minutes at Tahnoun Bin Mohammed Stadium before Omar Abdulrahman squared proceedings midway through the first half.
Alex Brosque gave the hosts the lead inside the first minute of the second half before former Sunderland striker Asamoah Gyan sealed the result in stoppage time.
Qatari side Al Rayyan played out a 3-3 home draw with Esteghlal of Iran in the group's other match.
Iranian champions Sepahan got their campaign off to a flying start as a Xhevahir Sukaj brace and a late Omid Ebrahimi strike sealed a 3-0 defeat of Dubai-based Al Nasr in Group C.
Last year's runners-up Al Ahli also made a winning start in the group with the Saudi side 2-0 winners against Qatar's Al Gharafa.