It's a tough draw for the A-League representatives.
Adelaide have been drawn with Pohang Steelers of Korea Republic, reigning AFC champions, and also face Chinese side Shandong Luneng and the eventual champions of the Japan Cup.
Melbourne return to the tournament to face Seongnam Ilhwa Chunma of Korea Republic, Beijing Guoan, where Newcastle Jets striker Joel Griffiths has recently returned from a successful loan stint, and Japanese side Kawasaki Frontale.
The top two teams, following the completion of the six rounds of group games, will progress to the Round of 16, a one-off elimination match before the finals commence.
The final two places in the draw, including one in Adelaide's Group H, will be decided in East and West Play-off matches.
Seongnam Ilhwa Chunma (Korea Republic)
Melbourne Victory (Australia)
Beijing Guoan (China PR)
Kawasaki Frontale (Japan)
Adelaide United (Australia)
Shandong Luneng (China PR)
Cup winners (Japan)
Pohang Steelers (Korea Republic)
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