Having won each of their four home games in the competition so far, Xavi’s Al Sadd needed to extend the run if they were to secure a last-four place, having lost 2-1 in Riyadh.

There was nothing to separate the two giants three weeks ago in Jeddah as Ittihad failed to score for the first time in the competition this year, while the stalemate meant Al Hilal had gone 180 minutes without finding the back of the net.

Both teams have stumbled in their last domestic appearance; Al Hilal were held to a 1-1 draw by Al Fayha on Saturday, while Al Ittihad were stunned 2-1 by newly promoted side Damac a day earlier.

Two first-half goals had stunned the home crowd at Shanghai Stadium last month when Tomoaki Makino and Shinzo Koroki gave visitors Urawa Red Diamonds a 2-0 lead at the break, but two penalties emphatically converted by Hulk after the restart saw the scores finish level in China PR.

With the away goal advantage and in front of their home support, Urawa have been left in a strong position to advance to the last four for the fourth time in seven appearances, while Shanghai SIPG would be looking to reach just their second semi-final.

Going into the matches, only Al Nassr start with a lead while the other three fixtures will kick off all square. Ahead of what promises to be an intriguing few days packed with drama and tension, the-AFC.com has picked five things to look out for.

Many of Urawa Reds current side know what it takes, and what it feels like, to be AFC Champions League winners. Less than two years ago, the likes of Shusaku Nishikawa, Tomoaki Makino and Shinzo Koroki lifted the trophy into the Saitama night sky.

Two from that squad, captain Yuki Abe and Tadaaki Hirakawa, had also won the title 10 years earlier; a success that had a profound impact on current defender Hashioka, the youngest player in the first team.

Urawa hold a slender advantage after the first leg of the quarter-final clash in Shanghai last month, when the two away goals earned in the 2-2 draw against Vitor Pereira’s side left the two-time champions needing only a low-scoring draw to advance to the last four for the fourth time since 2007.

Victory, of course, would take Urawa through but they will also advance should they notch up either a goalless draw or a 1-1 tie thanks to the goals scored by Tomoaki Makino and Shinzo Koroki in the first 45 minutes in China PR.

The last eight tie is finely poised after the first leg of the 'Saudi Clasico' ended 0-0 three weeks ago and Chilean Villanueva, speaking after Al Ittihad fell to a shock 2-1 defeat to Damac in the Saudi Pro League on Friday, said the Jeddah-based club can't afford a similar performance against Al Hilal.