Chelsea have been drawn against PAOK, BATE Borisov and Vidi in the Europa League.
The Blues won this competition in 2012/13 under Rafa Benitez and are competing in it for the first time since their victory over Benfica in May 2013.
Maurizio Sarri, who took Napoli to the round of 32 in last season's Europa League, said the competition creates a mad schedule but is something he values. "In terms of stress it’s on the edge of madness but it’s the secondary European competition and it always has charm," he said.
Greek side PAOK were on course for a place in the Champions League after an impressive 1-1 at Benfica in the first leg of the final play-off round, but a 4-1 defeat on home soil confined them to Europe's second-rate competition.
BATE Borsov were also one tie away from the Champions League group stage but were beaten by PSV Eindhoven.
Mol Vidi, Hungarian first division champions, began their Champions League qualification in July but were beaten by AEK Athens in the final round.
Matches begin 20 September and conclude 13 December.
