Estonia's Kusti Nõlvak and Mart Tiisaar were among the eight pool winners as main draw action began at the International Volleyball Federation Beach World Tour three-star event in Jūrmala.
The 12th-seeded duo opened their Pool E campaign on the Latvian city's Majori Beach by beating Spain's César Menéndez Ortego and Alejandro Huerta Pastor 21-10, 22-20.
They then defeated Germany's Philipp Arne Bergmann and Yannick Harms 21-17, 22-20 to secure a place in the second round of the knockout stage.
Nõlvak and Tiisaar's best results of the year are two quarter-final finishes, at three-star events in Sydney and Edmonton, and they are happy to again be progressing well through the main draw.
"It’s always really good to win and especially against such good opponents," Tiisaar said.
"We have played them in the past, I think we lost twice and won once, so we got a really decent result this time and it feels good."
Nõlvak added: "Mart played like a beast.
"He was smashing the ball so hard, getting in really good blocks, and I was just serving there and setting to him, so it was good."
Joining Nõlvak and Tiisaar in round two were top-seeded Latvians Mārtiņš Pļaviņš and Edgars Točs, who finished first in Pool A .
Pļaviņš and Točs came from behind to overcome Estonia's Timo Ander Lõhmus and Märt Tammearu 19-21, 21-15, 15-6 and then claimed a 21-16, 21-19 victory over Lithuania's Lukas Kazdailis and Arnas Rumsevicius.
Another home pairing, second-seeded Aleksandrs Samoilovs and Jānis Šmēdiņš, ended the day at the summit of Pool B after beating Poland's Marin Chiniewicz and Michal Korycki 21-19, 21-13, and Slovenia's Nejc Zemljak and Jan Pokeršnik 21-19, 21-18.
Pool C was won by Belarus' Aliaksandr Dziadkou and Pavel Piatrushka after they defeated third seeds Stafford Slick and William Allen of the United States 22-20, 21-13 in the decider.
An all-American match determined the winner of Pool F, with Casey Patterson and Chase Budinger overcoming Miles Evans and William Kolinske 21-17, 22-24, 15-11.
The other table toppers were fourth-seeded Swiss Nico Beeler and Marco Krattiger in Pool D, France's Quincy Aye and Arnaud Gauthier-Rat in Pool G, and Germany's Jonathan Erdmann and Sven Winter in Pool H.
Action in Jūrmala will resume tomorrow with all the round one matches, between the second- and third-place finishers in each pool.
They will be followed by the games in round two and round three, the last-16 and quarter-final stages.