In a cagey encounter between the Qatari and Iranian champions at Khalifa International Stadium, chances were at a premium all evening. Al Duhail had to eventually settle for the slender advantage provided by Ali's 15th-minute goal, which saw him head in at the back post following Edmilson's cross from the left.

The result meant that the Qatari champions matched Ulsan Hyundai's record of nine consecutive wins in the AFC Champions League.

Al Duhail nearly seized the initiative early on with front man Youssef El Arabi narrowly failing to connect with Nam Tae-hee's header across the goalmouth in the fourth minute.

In the 15th minute, the home side broke the deadlock through young striker Ali. Summer signing Edmilson sent in a teasing cross from the left and the unmarked Ali headed in with aplomb to get his second goal of the tournament.

Persepolis then came close to equalising in the 23rd minute, but Omid Alishah's effort flew just wide of Amine Lecomte's goal.

Losing 2-0 at Kashima Soccer Stadium was far from an ideal result for Chinese Super League side Tianjin Quanjian, especially after they had held the game goalless for an hour before Leo Silva, and then Serginho, struck for the hosts.

Nevertheless, former AC Milan star Alexandre Pato believes that the result is still not a foregone conclusion with the return meeting in China still to come in three weeks' time.

For the first time since the introduction of the East v West final in 2013, all four teams in the West Asian quarter-finals come from just two countries, offering us the opportunity to watch two tasty IR Iran v Qatar encounters, as Tehran giants Estaghlal and Persepolis face Al Sadd and Al Duhail respectively.

Throughout the years, teams from the two nations have produced some classics when they met. Here are four memorable matches between them from recent editions of the competition.

Proving that practice does indeed make perfect, Leo Silva's strike on the hour set J.League side Kashima on their way to a 2-0 first leg advantage in their last eight tie against visiting Chinese Super League side Tianjin Quanjian.

The rare goal for the defensive midfielder was very much one that was made on the training field.

The hosts began brightly and had an early sight on goal when Yasushi Endo headed wide from close in after a fine Koki Anzai delivery from the left, and the captain was again off target in the 14th minute as he drilled past the left post.

Go Oiwa’s team continued to dominate and Kento Misao had an effort saved by goalkeeper Zhang Lu, before Yuma Suzuki was inches away from connecting with a teasing Endo cross into the box as the game remained goalless.

The Algerian bagged a brace to help the 2011 AFC Champions League winners come from behind to defeat Esteghlal 3-1 at Azadi Stadium.

Young goalkeeper Meshaal Aissa failed to control a backpass, allowing the ball to go under him and into the back of the net to gift Esteghlal the opener.