Familiar foes meet again in Asia as the 2017 AFC Champions League semi-finals kick off on Tuesday and Wednesday. In the continent's west, Saudi giants Al Hilal entertain Persepolis in their seventh continental meeting. In the far east, meanwhile, both hosts Shanghai SIPG and Urawa Red Diamonds enter their third clash this year seeking to take the initiative, having won one apiece during the group campaign.

The matches Al Hilal-Persepolis This is a pairing that stands out as a classic considering the two sides' status among Asia's traditional powerhouses. And they are no strangers to each other, having met six times on the continental scene, including sharing the spoils in two matches earlier this season. Al Hilal enter the re-meeting with a slight mental edge, having boasted one more victory than their Iranian rivals.

Persepolis, however, will take heart from their only win two years ago when they triumphed at home by a solitary goal. The Tehran giants will look to Nigerian forward Godwin Mensha to get among the goals. Shouldering the goal-scoring tasks for the Riyadh side, meanwhile, is Brazilian hot-shot Carlos Eduardo, who is currently the team's top-scorer with seven goals.

Shanghai SIPG-Urawa Reds This match-up shapes a goalscoring spree with the two sides among the best scorers in this campaign. Urawa Reds, who memorably won the competition a decade ago, have racked up 23 goals out of ten outings while Shanghai SIPG are just three goals shy of that tally. Their group meetings proved evenly contested with each grabbing three points apiece.

The Japanese may have enjoyed the lion's share of possession, but the fast-developed C League side proved more threatening through their pacy attacks. Shanghai boast a formidable Brazilian trio in Hulk, Oscar and Elkeson, with the latter having won the Asian title twice with Guangzhou Evergrande. Urawa, for their part, can count on fan-favourite striker Shinzo Koroki, who has scored four times in this Asian campaign and is the leading scorer in the J.League.

Player to watch Shanghai SIPG supporters are all too aware that Brazilian forward Hulk's form could be key if their side is to win at home against Urawa Reds. The former Zenit and Porto goal-getter is currently topping the goalscoring chart with eight goals and he has proved more than capable of finding the back of the net in the two group matches against the Japanese giants, during which he produced five shots, three key passes and a goal and an assist. If he can reproduce the form that helped his side eliminate two-time winners Guangzhou Evergrande in the quarter-finals, Shanghai will mount a serious challenge.

Do you know? Both legs between Al Hilal and Persepolis will be played in neutral venues. The first leg sees the Saudi giants entertain the Iranians on Tuesday at Abu Dhabi’s Mohammed Bin Zayed Stadium in United Arab Emirates. Persepolis will then play hosts at the Muscat’s Sultan Qaboos Sports Complex in Oman.

What they said "To play in both the domestic league and the AFC Champions League is always a challenge. But we are proud of progressing to the last four in the Asian campaign. Al Hilal are a strong team and I had previously said they would qualify for this stage. We will continue to do our best and enjoy the matches." Persepolis coach Branko Ivankovic