Complex sentence: The most popular team is the city's football club, Olympique de Marseille, which was the finalist of the UEFA Champions League in 1991, before winning the competition in 1993 and finalist of the UEFA Cup in 1999 and 2004.
Split into simpler sentences: The most popular team is the city's football club, Olympique de Marseille, which was the finalist of the UEFA Champions League in 1991, before winning the competition in 1993. The club was also finalist of the UEFA Cup in 1999 and 2004.