Six-times European champion Francisco Gento drew the names from pot 4. The former Real Madrid star put AS Monaco in Group C.
Year founded: 1886
Honours: 33 Portuguese league titles - 2 European Cup titles
Home stadium: Estádio de la Luz (capacity: 65,647)
After finishing third in their group last season, Benfica went on to reach the final of the UEFA Europa League, where they were beaten on penalties by FC Sevilla. AS Monaco has never played the Lisbon club before in Europe.
Year founded: 1925
Honours: 3 Russian league titles - 1 UEFA Europa League title
Home stadium: Petrovski Stadium (capacity: 21,570)
Zenit overcame Standard Liège in the play-offs to book their place in the group stage. It will be the first competitive meeting between the two clubs.
Year founded: 1904
Honours: 1 UEFA Europa League title
Home stadium: Bay Arena (capacity: 30,210 places)
After their elimination at the hands of PSG in the round of 16 last season (0-4 and 1-2), Bayer Leverkusen return to the competition determined to improve on that peformance. In 1997-1998, AS Monaco eased past the German side in the group stage (4-0 and 2-2).
Valère Germain’s reaction to the draw