Defending champions Al Hilal were Tuesday drawn against UAE's Al Ahli and Uzbekistan's Pakhtakor for the start of their campaign for a record fourth Asian club title in the AFC Champions League.
The Saudi giants beat Japan's Urawa Red Diamonds last month, ending a 19-year wait for their third continental trophy and joining South Korea's Pohang Steelers as the only three-time Asian champions.
They also became the competition's first West Asian winners since Qatar's Al Sadd in 2011, torpedoing a run of victories by clubs from Japan, South Korea, China and Australia.
Two-time winners Guangzhou Evergrande of China, who won the Chinese Super League title this month, will face South Korean side Suwon Samsung Bluewings after being drawn in the same group at the Asian Football Confederation (AFC) headquarters in Kuala Lumpur.
Meanwhile, South Korea's Jeonbuk Motors, who have also clinched the title twice, will face Yokohama Marinos of Japan and Australia's Sydney FC.
Ulsan Hyundai, champions in 2012, were drawn with Shanghai Shenhua from China and Australian side Perth Glory.
"It is quite an evenly balanced" draw, AFC general secretary Windsor John told AFP. "We look forward to another thrilling campaign."
The 2020 season begins with the preliminary stage in January, with the two-leg final scheduled for November.
The AFC Champions League will feature 32 teams in 2020 for the final time, with the tournament set to expand to 40 sides from 2021.
Group A: Al Wahda (UAE), Al Shorta (IRQ), play-off winner, play-off winner
Group B: Al Hilal (KSA), Al Ahli (UAE), Pakhtakor (UZB), play-off winner
Group C: Al Duhail (QAT), Al Taawoun (KSA), Sharjah (UAE), Persepolis (IRN)
Group D: Sepahan (IRN), Al Sadd (QAT), Al Nassr (KSA), play-off winner
Group E: Beijing (CHN), Chiangrai United (THA), play-off winner, play-off winner
Group F: Ulsan Hyundai (KOR), Shanghai Shenhua (CHN), Perth Glory (AUS), play-off winner
Group G: Japan 2nd Club, Suwon Samsung Bluewings (KOR), Guangzhou Evergrande (CHN), Johor Darul Ta'zim (MAS)
Group H: Sydney FC (AUS), Yokohama Marinos (JPN), Jeonbuk Motors (KOR), play-off winner