Qualification top seeds Nuttanon Inkiew and Sedtawat Padsawud of Thailand failed to reach the main draw of the International Volleyball Federation Beach World Tour event in Jūrmala, losing to Poland's Martin Chiniewicz and Michal Korycki.
Inkiew and Padsawud went straight through to round two of qualification, but fell to a 19-21, 16-21 defeat on the Latvian city's Majori Beach.
Chiniewicz and Korycki, the 16th seeds, had earlier defeated Norway's Jørn Olav Gamlemoen and Christian Helland 21-12, 21-16 in round one.
Qualification second seeds Armin Dollinger and Eric Stadie of Germany will join the Polish duo in the main draw after defeating Norway's Svein Oddmund Solhaug and Christian Jørgensen Ruud 21-18, 21-18.
Among the other six teams advancing were fourth-seeded Lithuanians Artur Vasiljev and Robert Juchnevic, sixth-seeded Norwegians Daniel Bergerud and Lars Tveit Retterholt, and seventh-seeded Danes Mads Rosager and Jacob Stein Brinck.
Also progressing are eighth-seeded Slovenians Vid Jakopin and Tadej Bozenk, 14th-seeded Germans Dirk Westphal and Lukas Pfretzschner, and 21st-seeded Estonians Timo Ander Lõhmus and Märt Tammearu.
Westphal and Pfretzschner upset the odds to beat third-seeded Danes Martin Trans Hansen and Kristoffer Abell 21-19, 13-21, 18-16.
Lõhmus and Tammearu also claimed a shock 21-15, 17-21, 18-16 win over fifth-seeded Latvians Toms Šmēdiņš and Haralds Regza to the disappointment of the home crowd.
The main draw, starting tomorrow, will be in a 32-team modified pool play format, with 24 teams advancing to single elimination.