Stoyanovskiy and Yarzutkin battled to a hard-fought 21-17, 18-21, 15-8 triumph over Belgium's Dries Koekelkoren and Tom Van Walle to reach the last four on Kish Island for the second year in a row.

It will also be the second consecutive semi-final appearance for Kantor and Losiak, who comfortably beat Australia’s Cole Durant and Zachery Schubert 21-16, 21-7.

The Russian pair will be hoping to go one better than last season's corresponding tournament in Iran, where they lost in the final to Qatar's Cherif Younousse and Jefferson Santos.

The other last four encounter will be between Russia’s Nikita Liamin and Viacheslav Krasilnikov and the German pairing of Lorenz Schumann and Julius Thole.

Liamin and Krasilnikov maintained the impressive performance form Russian players at the all-male event with a 26-24, 17-21, 15-10 success over team-mates Maxim Sivolap and Igor Velichko.

Schumann and Thole emerged victorious from their all-German clash with Markus Bockermann and Lars Fluggen as they claimed a 21-19, 12-21, 15-12 win.

Younousse's title defence with new partner Júlio César Do Nascimento Júnior had moved a step closer when they took the opening set of their round of 16 clash with Sivolap and Velichko before the Russians bounced back to earn an 18-21, 21-14, 15-13 victory.

The four-day three-star competition is for male players only and will conclude with the semi-finals and final tomorrow.

A law restricting female access was introduced at volleyball matches in Iran in 2012 as an extension of a similar ban in football, but when contacted by insidethegames, the FIVB confirmed all members of the public will be able to attend this year’s event.