2013 AFC Champions League knock-out stage
The knock-out stage of the 2013 AFC Champions League was played from 14 May to 9 November 2013. A total of 16 teams competed in the knock-out stage.
The winners and runners-up of each of the eight groups in the group stage qualified for the knock-out stage. Both West Asia Zone and East Asia Zone had eight teams qualified.
In the knock-out stage, the 16 teams played a single-elimination tournament. Each tie was played on a home-and-away two-legged basis. The away goals rule, extra time (away goals do not apply in extra time) and penalty shoot-out were used to decide the winner if necessary.
The schedule of each round was as follows.
In the round of 16, the winners of one group played the runners-up of another group in the same zone, with the group winners hosting the second leg. The matchups were determined as follows:
The draw for the quarter-finals, semi-finals, and final (to decide the order of two legs) was held on 20 June 2013, 16:00 UTC+8, at the AFC House in Kuala Lumpur, Malaysia. In this draw, teams from different zones could play each other, and the "country protection" rule was applied: if there are exactly two teams from the same association, they may not play each other in the quarter-finals; however, if there are more than two teams from the same association, they may play each other in the quarter-finals.
The first legs were played on 14 and 15 May 2013, and the second legs were played on 21 and 22 May 2013.
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