Host Australia takes on an China on Thursday in the most anticipated of the quarterfinal matches at the Asian Cup, while two-time champion South Korea meets 2011 semifinalist Uzbekistan.
Here's some things to watch:
AUSTRALIA VS. CHINA (1030 GMT)
Australia should be boosted by the return of captain Mile Jedinak, after the Crystal Palace skipper missed the past two games due to injury.
"It's going to be great to have him back," Australia coach Ang Postecoglou said Wednesday. "He's our most influential player when he's out there and I'm sure it will give all the other players a lift."
Several key players who were rested for the loss to South Korea in the last group-stage game are also in the frame to return in Brisbane: Tim Cahill, Robbie Kruse and Matthew Leckie. Those players should help Australia get back to the attacking potency that saw the Socceroos score four goals in each of their first two games before drawing a blank against the Koreans.
China should have captain Zheng Zhi available despite the back injury he sustained against North Korea; a game the Chinese won to complete a perfect group stage of three wins from three games. However there is concern over the availability of central defender Zhang Linpang, who has a calf strain. China coach Alain Perrin said it will likely be a game-day decision on whether Zhang can play. With Australian attacking duo Cahill and Tomi Juric posing a strong aerial threat, China can ill afford to lose its defensive lynchpin.
China has the edge in recent contests against Australia, winning two and drawing one of the past three meetings, and did have the better group-stage record, but Postecoglou dismissed that.
"You don't get an extra chance just because you won your three group games," Postecoglou said. "The previous records are now extinguished ... even the ones that have won their three games, they won't be sitting any more comfortably in this phase."
SOUTH KOREA VS. UZBEKISTAN (0730 GMT)
South Korea topped Group A by beating Australia 1-0 in the last game, making the Koreans one of four teams to complete pool play with a perfect record. It also maintained a flawless defensive record, having kept a clean sheet in all three games. The defensive strength has, however, been a requirement rather than a bonus, as the team only scored three goals in the group stage, despite boasting creative talent such as Bayer Leverkusen's Son Heung-min. The lack of attacking coherence may in part be due to the injuries and illness which have hampered the South Korean squad through the tournament, forcing coach Uli Stielike to use 22 of his 23-man squad. Son missed the last group game due to illness, but is expected to be fit for the game in Melbourne.
Uzbekistan needed a victory in its last group-stage game in order to reach the knockout stages and withstood the pressure _ plus some contentious refereeing decisions _ to beat Saudi Arabia 3-1. Coach Mirjalol Qosimov blasted the Saudi players after the game for repeated instances of simulation which made life difficult for the referee.
South Korea is a perennial power in Asian football, at national team and club level, yet has not won the Asian Cup since its second edition in 1960, having lost three finals since. The South Koreans have only lost to Uzbekistan once. But the two teams are evenly matched, as demonstrated in the qualifying for the 2014 World Cup when the they played to a 2-2 draw in Tashkent and South Korea eked out a 1-0 win at home.