Japan maintained their pursuit of a record-extending fifth Asian Cup title on Wednesday by advancing to the quarter-finals with a 3-1 win against Bahrain.
The pre-tournament favourites have bounced back from a surprise 2-1 loss against Iraq in the group stage and will play Iran in the next round.
Goals from Ritsu Doan, Takefusa Kubo and Ayase Ueda secured Japan's place in the last eight, while Zion Suzuki's own goal was the only consolation for Bahrain.
Japan went ahead in the 31st minute when Seiya Maikuma's long-range shot came back off the post and Doan converted on the rebound.
Kubo doubled the lead four minutes into the second half when he spun and finished from close range.
The Japan goalkeeper then tried to catch the ball, but collided with Ayase, who was attempting to head clear off the goal-line and the ball was fumbled into the net.
Ayase restored Japan's two-goal advantage eight minutes later when firing low at the near post to beat Bahrain keeper Ebrahim Lutfalla.
Three-time champions Iran later needed a penalty shoot-out to beat Syria, one of the tournament's surprise packages.
Down to 10-men after Mehdi Taremi was sent off in time added on, Iran eventually won 5-3 on spot-kicks at Abdullah bin Khalifa Stadium. The game ended 1-1 after extra time.
Taremi fired Iran ahead with a penalty in the 34th after he had been fouled by Aiham Ousou.
Syria then equalised from the spot through Omar Khrbin in the 64th minute after Pablo Sabbag was brought down by Iran keeper Alireza Beiranvand.
Syria were playing in the knockout stage of the Asian Cup for the first time and were given an advantage when Taremi was sent off in the first minute of stoppage time for a second bookable offence.
In the shoot-out, Beiranvand's save from Fahd Youssef proved the decisive moment as Iran converted all of their spot kicks. It is the eighth time in a row that Iran have advanced to the quarter-finals.