The draw means Iran beat Iraq to first place in group D via goal difference as both teams finished with seven points each.
Iraq will play the winner of group E, either Qatar or Saudi Arabia, in the Round of 16; this will be determined on Thursday after the Gulf nations face each other in their final group match.
Iran, meanwhile, will play the best third-place team from either group B, E, or F.
The last time Iraq and Iran met was at the quarter-finals of the 2015 Asian Cup.
After a thrilling 3-3 draw, the Iraqis defeated the Iranians 7-6 on penalties.
The Iraqis went on to lose their semi-final match 2-0 against South Korea.
The 2019 Asian Cup began on Jan.
5 and will continue until Feb.
For the first time, Asia’s largest continental tournament includes 24 teams instead of the traditional 16-team format used in previous competitions.
Iraq’s most notable triumph at the international level came in 2007 when they were crowned Asian Cup champions, beating Saudi Arabia 1-0 in the final.
Iraq is 88th in FIFA’s world rankings (their highest ever rank was 39 in 2004).
They have failed to qualify for the FIFA World Cup since their maiden appearance at the Mexico 1986 tournament where they lost all three of their group matches.