Clubs from Lithuania, Georgia, Moldova and Macedonia on Tuesday became the first four to progress from 11 Champions League first qualifying round ties.
Lithuanian champions FK Ekranas beat KS Elbasani of Albania 3-0 in their second-leg match to go through 3-1 on aggregate and reach the second qualifying round for the first time.
Ekranas will next play Croatia's Dinamo Zagreb.
Georgian side FC Sioni Bolnisi went through 2-1 on aggregate despite losing 1-0 in Azerbaijan to FK Baku and face Levski Sofia of Bulgaria in the next round.
Moldovan champions FC Sheriff have landed a plum tie with Spartak Moscow after winning 2-0 against Armenia's FC Pyunik, both on the night and on aggregate. It is the sixth time in a row that they have got past the first qualifying round.
Macedonian champions FK Rabotnicki progressed 1-0 on aggregate against F91 Dudelange thanks to last week's narrow win in Luxembourg after Tuesday's goalless draw at the Gradski stadium in Skope. Rabotnicki next face Hungary's Debrecen.
The remaining seven ties in the first qualifying round will be played on Wednesday.