Carlos Queiroz's men eased through the group phase unbeaten and things ended up being similarly comfortable, despite getting off to a rocky start.

Gulf Cup champion Oman saw an early Ahmed Al Mahaijri penalty saved and they were made to rue that missed opportunity, as Jahanbakhsh's strike and Dejagah's spot-kick had Iran in control at half-time.

Although Iran was unable to convert any of its further chances, Oman failed to produce an unlikely comeback, as Queiroz's side heads into a last-eight clash with China having not conceded a goal in the tournament.

Oman had a chance to take an early lead when Seyedmajid Hosseini clumsily tripped Muhsen Al Ghassani in the area, but Alireza Beiranvand made a fine save down to his right to keep Al Mahaijri's attempt out.

Iran took advantage just after the half-hour mark, Jahanbakhsh punishing Mohammed Al-Musallami's error by slotting past Faiyz Al Rusheidi.

The goalkeeper was helpless again just before the break – Dejagah converted the game's second penalty confidently down the middle after Saad Al-Mukhaini was controversially adjudged to have fouled Mehdi Taremi.

Iran's dominance only appeared to grow after the break. Sardar Azmoun blazed over from 12 yards in the 52nd minute, before Taremi's fierce volley was well saved by Al Rusheidi.

The Oman goalkeeper made another commendable stop late on to thwart Taremi in a one-on-one situation, though it made no difference to the triumphant Iran.