Saudi Arabia take on Iraq in a second game packed with sporting rivalry, while North Korea play United Arab Emirates and Thailand do battle with Jordan in the other games.
Matches between South Korea and Japan often produce fireworks given the historical animosity between the countries. Their latest meeting will have extra edge with the Koreans under intense pressure to end a 28-year gold medal drought on home soil.
South Korea's players have the added incentive of being excused two years of mandatory military service if they win the title in the under-23 tournament. But Japan are testing a new young side for the 2016 Olympic qualifiers and could spring a surprise. (Japanese Swimmer Kicked Out for Stealing Camera)
Defeat by defending champions Japan would be seen as a national humiliation in South Korea.
It could also provoke an angry response from fans, who greeted South Korea's World Cup flops by throwing toffees at them on their return -- a traditional insult in the country, where "Go eat a toffee!" translates as a fruitier version of "Get lost!"
South Korea's full side lost all three group games at the World Cup finals in Brazil.
"We wanted to play South Korea," Japan coach Makoto Teguramori told reporters. "It doesn't getter any better than this," he added. "Imagine us beating them and winning gold on their turf."
A South Korea player inflamed a diplomatic row with Japan over a territorial dispute by waving a political flag after the Koreans beat Japan 2-0 in the bronze medal match at the 2012 London Olympics.
With relations between Tokyo and Seoul icy cold, the potential remains for a similar outpouring of patriotism over disputed islets called Dokdo by South Korea and Takeshima in Japan.
South Korean coach Lee Kwang-Jong will hope towering striker Kim Shin-Wook, whose ever-changing hairstyles are closely watched by local fans, has recovered from a calf injury to make an impact.
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"He's not 100 percent but he could also come off the bench," Lee said of the wildcard pick.
"Korea and Japan are arch-rivals but the players are mentally ready," he added.
There will be little love lost in the Arab clash between Iraq and Saudi Arabia either, both sides looking to the future after differing fortunes in recent years.
War-torn Iraq, Asian Games champions in 1982 in New Delhi and silver medallists in Doha eight years ago, have ridden the crest of a wave over the past decade.
Their country's so-called "golden generation" reached the 2004 Olympic semi-finals and lifting the 2007 Asian Cup and they could also have a psychological edge over the Saudis after beating them 1-0 in the final of the Olympic Asian Cup earlier this year.
Iraq, unable to play home games in their country due to safety fears, are daring to dream after overcoming Tajikistan 4-2 to reach the last eight.
Three-times Asian Cup winners Saudi Arabia, who scraped past Uzbekistan 3-2 on Friday, are in the rebuilding stage after suffering a barren run in recent years.
"We beat the Saudi team twice at the Olympic Asian Cup in Oman," said assistant coach Adnan Safaa. "But just because we won the title doesn't mean we will not be wary of them tomorrow. They are a strong team and we expect a great game."