And teams that come 4th in the league are knocked out. The team in 3rd are knocked out and join the Europa League, and after the group stages it is a straight knock out competition.
And if you lose your first 3 games 10-0 you're guaranteed another 3 games. It is clearly both a league and a knockout competition, so to say a team that wins 'doesnt deserve it' is preposterous. They have to overcome BOTH elements of competition.

