competition, is contested in pure "knockout" format since its inception in 1989. While the top two tiers in the Brazilian League – Série A and Série B – are contested in double round robin format, the lower tiers Série C and Série D include knockout rounds in their final stages. Bulgaria Bulgaria instituted an elaborate playoff system in its top flight, the First League, in the 2016–17 season. After the league's 14 teams play a full home-and-away season, the league splits into two playoffs—a 6-team "championship playoff" and an 8-team "qualifying playoff", with the latter split into two 4-team groups. Each playoff begins with teams carrying over all goals and statistics from the home-and-away season. Each team in the championship playoff plays the others home and away one additional time. At the end of this stage: The top team is declared league champion, and earns the country's sole place in the UEFA Champions League. The second-place team earns a place in the UEFA Europa League. The highest-placed team that has not already qualified for European competition advances to an eventual one-off match for the country's final Europa League place. This will often be the third-place team, but if the winner of the Bulgarian Cup (which earns an automatic Europa League place) is in the top three of the playoff, the fourth-place team will take its place. Each group within the qualifying playoff also plays home and away within its group; after this stage, teams enter another level of playoffs depending on their positions in the group. The top two teams in each group enter a knockout playoff consisting entirely of two-legged matches (unless one of these teams is the winner of that season's Bulgarian Cup, in which case it will not enter the playoff and the team that it would have played receives a bye into the playoff final). The winner of this playoff then contests a one-off match against the third-place (or fourth-place) team from the championship playoff, with the winner claiming the final Europa League place. The bottom two teams from each group begin a series of relegation playoffs. The series starts with a knockout playoff that also consists entirely of two-legged matches. The winner of the playoff remains in the First League for the following season. The losing teams then enter the following series of two-legged promotion/relegation matches: The losers of the knockout semifinals play, with the