Everything you need to know about how Champions League extra time works.
The UEFA Champions League knockout stage is in full swing, meaning we might see some extra time as the field narrows down.
In the group stage, teams can draw, but in the knockout rounds, someone has to go down. In the first leg of a two-legged round, a game can end as a draw. In the second leg, ties are given to the team with the most away goals over the course of both legs.
If the two sides have the same number of away goals after two legs of play, the match goes to extra time.
Extra time consists of two 15-minute periods, no matter what—there's no golden goal rule. The away goals rule continues to apply here, so if the away team scores in an extra time, the home team must score twice to break the deadlock.
If the two teams remain level through all that, then the match goes to penalty kicks. Penalties are best of five, with teams taking turns until one team mathematically cannot win. If teams are level through five penalties, they keep going until the tie is broken (on the same turn, someone scores and someone else does not).
The Champions League regularly features extra time. In last year's competition, Bayern Munich beat Juventus in extra time in the round of 16, while Atletico Madrid needed penalties in the round of 16 to advance past PSV Eindhoven. Atletico ultimately reached the final, where the team lost to Real Madrid on penalties after a scoreless extra time.