Each competitions have viewed format improvements, with expansions in the number of collaborating teams, introduction of latest rounds, and changes in qualification standards over the years. The group stage was played from September to December, whilst the knockout phase commenced in February, with matches ordinarily performed on Tuesday and Wednesday https://k-o-nh-c-i-chu-n28406.goabroadblog.com/35376722/about-what-are-the-uefa-champions-league-and-uefa-europa-league