The Poles triumphed 25-20, 25-19, 25-19 to earn gold at this tournament for the second time after a success in 2015, while Bulgaria’s silver is their first medal since securing bronze at the inaugural edition in Dubai in the United Arab Emirates in 1989.

The Polish team only dropped one set in the whole tournament, cruising past Nigeria, India and Iran in the preliminary round's Pool A, and then Guatemala and Colombia in the round of 16 and quarter-finals respectively - all in straight sets.

In yesterday’s semi-final, Poland met Iran again in what proved a close contest, but they came out on top 26-24, 25-23, 23-25, 25-20.

Other ranking matches were held earlier in the day, with hosts Iran securing a victory over Russia in a deciding tiebreak to deny their opponents a podium finish for the first time since 2013.

Russia’s Timofei Tikhonov top scored with 23 points, but 41 unforced errors from his side proved costly.

Poriya Khanzadeh of Iran notched 18 points, including five aces, to earn his country’s seventh medal at the FIVB Boys' Under-19 World Championship with a 25-14, 22-25, 27-25, 21-25, 15-6 victory.

Fifth place went to Argentina as they came from behind to defeat Italy, who went into the tournament as defending champions, 18-25, 25-20, 25-19, 25-21.

Brazil clinched seventh place after beating Germany 25-17, 23-25, 26-24, 26-24, while the Czech Republic secured ninth with a 25-21, 25-16, 22-25, 25-16 win against India.

In the match for 11^th, Belgium recovered from losing the first set to see off Egypt 23-25, 25-14, 25-19, 25-23.

A five-set thriller saw Thailand stave off a fightback from Nigeria to finish 13^th, winning 25-15, 25-20, 17-25, 26-28, 15-13.