Persepolis striker Mehdi Taremi's second-half strike was enough for Iran to edge out Qatar 0-1 on Thursday in a 2018 World Cup qualifier at the Jassim Bin Hamad Stadium in Doha.
The result sees Iran go four points clear in Group A with a total of 14 points from six games while Qatar remained rock bottom with four points.
Carlos Queiroz's side were the only undefeated team in Group A of the third round of qualifying and continued that record with another fine away performance.
Iran went into the game knowing that they will be able to extend their lead, courtesy of a shock defeat of South Korea at the hands of China earlier in the day.
The game got off to a pulsating start with both sides fashioning goalscoring opportunities but an opener evaded them in the first half. FC Rostov forward Sardar Azmoun was a livewire in the Iranian attack in the early exchanges. The highly-rated youngster forced Qatari custodian Saad Al Sheeb to deny him twice inside the opening forty-five minutes.
The two sides went into the break level on the scoresheet but it was the visitors who had enjoyed the best chances.
Seven minutes after the restart, Iran got their just rewards as Mehdi Taremi found the breakthrough. The tall striker, who has been in good form for his club recently, broke the offside trap and controlled Karim Ansarifard's long ball from midfield perfectly before placing a finish expertly past Al Sheeb.
Iran had further chances to kill the game off with Azmoun and Ehsan Hajsafi squandering easy offerings. They almost paid the price for those misses when Qatar came close to grabbing an equaliser in stoppage time through Sebastian Soria. But his effort was thwarted by Iranian goalkeeper Alireza Beiranvand.
This win has given Carlos Queiroz's team some breathing space after a draw in the last round had seen South Korea close in on them. But Thursday's win, coupled with other results going their way, would have made the former Manchester Untied assistant manager a very happy man.