The Norwegian pair were in commanding form as they stormed through the first set 21-13, before clinching the match with an equally comfortable 21-14 second set againt Czech duo Marcel Mysliveček and Martin Pihera in this four-star event. 

The top seeds were given a sterner test by seventh seeds Alexander Brouwer and Robert Meeuwsen from The Netherlands.

Despite claiming the first set 21-14, the Dutch came back to level the match, outscoring their rivals 23-21.

However, Mol and Sørum had too much in the tank and edged out Brouwer and Meeuwsen 28-26 in the deciding set.

The Dutch pairing had earlier defeated Belgians Dries Koekelkoren and Tom Van Wall 21-12, 21-18.

Spain's Adrian Gavira and Pablo Herrera remained on course to defend their Ostrava Beach Open crown.

First, they defeated Germany's Philippe Arne Bergmann and Yannick Harms 25-23, 23-21 in a closely-fought battle before edging out Latvian duo Martins Plavins and Edgars Tocs.

The 16th seeds Ondrej Perusic and David Schweiner, representing home country Czech Republic, surprised fourth seeds Aleksandrs Samoilovs and Janis Smedins, from Latvia, 21-13, 21-18.

Olympic champion Bruno Oscar Schmidt made a winning start in Pool G.

Schmidt lines up in Ostrava alongside Brazilian compatriot Evandro Gonçalves Oliveira Júnior and they enjoyed back to back wins as they seek the gold medal.

Schmidt's Olympics winning partner, Alison Cerutti, who now partners Álvaro Morais Filho, also recorded two victories.

Having eased to victory in their first Pool D match, getting the better of fellow Brazilians Andre Loyola Stein and George Souto Maior Wanderley, the in-form pairing edged out Qatari fifth seeds Cherif Younousse and Ahmed Tijan.

In the women's tournament there were mixed fortunes for the American pair of Kerri Walsh Jennings and Brooke Sweat, winners of the Jinjiang Open earlier this week.

Their triumph in China saw them become the oldest women’s team to win an FIVB Beach World Tour gold medal.

But, having dispatched of Chinese pair Fan Wang and Xinyi Xia in straight sets, they came undone against compatriots Alexandra Klinemann and April Ross, who landed a memorable 18-21, 21-16, 17-15 triumph.

Top-ranked Canadians Heather Bansley and Brandie Wilkerson had a much more enjoyable day in Pool B with two wins.

Barbora Hermannová and Markéta Sluková are bidding to retain the title they claimed on home soil last year, but lost their opening Pool match 18-21, 18-21 against Ukrainians Diana Lunina and Maryna Samoday

The competition is due to continue tomorrow and conclude with the medal matches on Sunday (June 2).