The eventual winners of the last 16 tie - the return leg will be played on August 12 - will face either Al Ahli Saudi FC or Al Hilal SFC in the quarter-finals.

The defeat was Zobahan's first in the 2019 AFC Champions League, having won three and drawn three matches in the group stage.

Al Ahli finished second behind Al Sadd in Group D, while Al Hilal topped Group C to set up the first AFC Champions League clash between the two sides and the fourth all-Saudi Round-of-16 tie in the competition’s history.

Al Sadd ultimately sealed the league title with a seven-point margin over runners-up Al Duhail, while the latter stormed to a 4-1 victory over their rivals to lift the Amir Cup trophy.

Both sides had reached the 2018 AFC Champions League knock-out stages, before being eliminated by eventual finalists Persepolis, who defeated Al Duhail in the quarter-finals and Al Sadd in the semi-finals.

A legend moving into the hot seat, a strong Saudi presence and plenty of new arrivals are among the talking points, so join the-AFC.com as we pick out five things to look out for.

Ahead of West Asia's Round of 16 first leg encounters, the-AFC.com looks at eight players who could make the difference for their respective teams.

Youth is the name of the game in West Asia this year as six of the eight AFC Champions League Round of 16 sides are led by head coaches younger than 50. With four new appointments and four continuing from the group stage, we are set to see some mouthwatering tactical battles over the next two weeks.

As a hot summer across West Asia comes to an end, it has also been a heated season in the transfer market. The eight teams from Saudi Arabia, United Arab Emirates, Islamic Republic of Iran and Qatar bolstered their ranks with exciting signings who hope to start with a bang as teams kick-off their season with the 2019 AFC Champions League Round of 16 matches in August.