Goals from Sardar Azmoun and Mehdi Taremi and yet another clean sheet ensured Iran became the first Asian nation to book their place at next year's World Cup as a 2-0 win over Uzbekistan on Monday evening secured Carlos Queiroz's team a berth in Russia.
Azmoun put his side in the lead in the 23rd minute before a goal from Taremi sealed Iran's progress to next year's finals two minutes from time.
The Iranians join Brazil as the only nations to have qualified for Russia 2018 so far, with Azmoun scoring midway through the first half to put Iran on track to qualify for the World Cup for the fifth time in the country's history.
Iran will also be appearing at back-to-back World Cups for the first time in the nation's history, having previous played at the finals in 1978, 1998, 2006 and 2014, but having never progressed beyond the group stages of the competition.
Security was tight at the Azadi Stadium ahead of the game in light of the recent terrorist attacks in Tehran, and the imposing venue took time to fill up to its usual levels.
There were few problems on the field for Iran, however.
As has been the case throughout the campaign, Queiroz's team stifled their opposition, giving little away in front of goal as they continued a remarkable streak of not conceding in qualifying that stretches back all the way to November 2015.
Allied to a striker of Azmoun's quality, Iran's defensive solidity has seen them move through the current phase of Asia's campaign with few troubles and Monday's win was the 11th game in a row the Iranians have completed without conceding.
Despite knowing a win would book their place in Russia, the Iranians started the game in a controlled fashion and in the 23rd minute Azmoun showed his cool head in front of goal to put his side in front.
The Rostov striker was found by Alireza Jahanbaksh's perfectly weighted pass that split the Uzbekistan defence and left Azmoun one-on-one with goalkeeper Aleksandr Lobanov. As Lobanov advanced, Azmoun slotted the ball under the keeper to give Iran a precious lead.
The Uzbeks pressed for the equaliser but against a defence as well-drilled as Iran's the visitors struggled to create many clear-cut openings.
Five minutes into the second half, Masoud Shojaei squandered the chance to double his side's lead when Taremi was felled in the penalty area, only for the veteran midfielder to sky his penalty woefully over the bar.
Iran rarely looked in danger of giving up their advantage and, with two minutes remaining, Taremi made sure of his team's progress to the finals.
The Persepolis forward powered into the area before stepping inside the Uzbekistan defence to curl a fine finish beyond Lobanov and into the far corner that sent the Azadi Stadium into wild celebrations.