Atalanta denied Massimiliano Allegri victory in his last home game in charge of Juventus, holding the Serie A champions to a 1-1 draw.
Slavia Prague have been punished for a series of incidents during their Europa League tie against Genk last month.
A complaint lodged by Chelsea regarding alleged racist abuse of Callum Hudson-Odoi at Dynamo Kiev will be investigated by a UEFA inspector.
Friday's Europa League draw saw the two Premier League sides kept apart in the last eight. Take a look at the full list of fixtures.
Chelsea and Arsenal were kept apart in the Europa League quarter-final draw, with the Gunners facing Napoli in the last-eight.
If Arsenal and Chelsea are drawn at home on the same day in the Europa League, the Gunners will have their fixtures reversed.
Chelsea will face Arsenal in the Europa League final after prevailing on penalties against Eintracht Frankfurt in London on Thursday.