Each competitions have viewed format improvements, with expansions in the number of collaborating groups, introduction of new rounds, and changes in qualification criteria through the years. The team phase was played from September to December, while the knockout stage began in February, with matches generally played on Tuesday and Wednesday https://cristianushqq.onesmablog.com/detailed-notes-on-what-are-the-uefa-champions-league-and-uefa-europa-league-77240497