Uzbekistan's Bunyodkor provided the biggest upset of this year's fledgling Asian Champions League when they shocked J-League title-holders Sanfrecce Hiroshima 2-0 away on Wednesday.
Despite last year's run to the semi-finals the Uzbek cup winners were considered underdogs against the Japanese champions, but a late goal in each half made them worthy winners in Hiroshima.
Oleksandr Pyshur struck on the stroke of half-time to put the visitors ahead but it wasn't until the 86th minute that Bunyodkor could be sure of the win, when Fozil Musaev doubled their advantage.
The victory extends Bunyodkor's fine form in the Asian competition after they overturned three former champions last year before being halted by eventual winners Ulsan Hyundai in the last four.
Elsewhere on day two, Kashiwa Reysol registered the first Japanese win when ex-Guangzhou Evergrande striker Cleo, returning to China to face Guizhou Renhe, was on target in the first half to secure a 1-0 victory.
The 2009 winners Pohang Steelers were held 0-0 by Beijing Guoan, while Australia's Central Coast Mariners and Suwon Bluewings also finished goalless in Gosford.
Iranian champions Sepahan cruised to a 3-0 win over Al Nasr of the United Arab Emirates with Albanian striker Xhevahir Sukaj scoring twice and Omid Ebrahami adding a third with four minutes remaining.
Saudi Arabia's Al Ahli also enjoyed a winning start in Group C, beating Al Gharafa of Qatar 2-0.
In Group D, UAE side Al Ain, the inaugural winners of the tournament in 2003, came back from a goal down to defeat 10-man Saudi outfit Al Hilal 3-1 with Australian striker Alex Brosque and Ghana star Asamoah Gyan among the scorers.
In Doha, Al Rayyan shared a six-goal thriller with the Qataris coming back three times for a share of the spoils against Esteghlal of Iran.