A place in the quarter-finals beckons as the much-anticipated 2012 AFC Champions League Round of 16 commences on Tuesday and Wednesday. The one-off knockout phase lasts two weeks, with eight West Asian teams battling against each other first, and the rest of the teams fighting for the remaining four spots a week later.

Saudi Arabia and Iran take centre stage in the first matchday, each boasting three teams in the last 16. Topping their list are some of the tournament's most experienced sides in the likes of newly-crowned Iranian champions Sepahan and Saudi duo Al Ittihad and Al Hilal, all of whom are playing in their eighth Asian finals.

Sepahan entertain Esteghlal in an all-Iranian affair, while Al Ittihad welcome Persepolis. Challenging Al Hilal are tournament debutants Bani Yas, and Al Jazira play hosts to Al Ahli hoping to continue their impressive form. Join FIFA.com as we preview the mouth-watering showdowns.

The match
Al Ittihad - Persepolis
Each time clubs from Saudi Arabia and Iran meet a classic encounter is in prospect. Indeed, this match-up is of true continental class with Al Ittihad the two-time AFC Champions League winners and Tehran giants Persepolis the victors in the 1991 Asian Cup Winners Cup. Having stormed into the final on three occasions, the Saudi hosts should have a mental edge over the Iranians, who have never progressed beyond the group stage in their three previous appearances. However, the visitors can take heart from a 3-2 win in their group meeting last year, although the Jeddah giants won the other encounter 3-1.

Despite a disappointing fifth-place finish in the Saudi league, Al Ittihad’s form in Asia has been markedly different winning their group unchallenged. Under Spanish coach Raul Caneda, they have fixed their sights on completing an Asian treble. "Our target is to go as far as we can," the former Real Sociedad mentor said. “Maybe we can win the competition." Persepolis, too, enter the match hoping to push aside their miserable domestic form which saw them finish 12th in the Iran Pro League. Boosted by a good showing in the group campaign, coach Mustafa Denizli is confident they can upstage the hosts. He said: "I believe we can go all the way. Whatever our next game, we will do whatever is worthy of our name."

The other attractions
In addition to the Persepolis game, Iranians fans will be treated to another enticing match-up which features their league and cup winners. Hot off their successful title-defense in the Iranian league, during which they edged Esteghlal by a point to clinch their third league title in a row, Sepahan are now seeking to translate their domestic form onto the Asian front against the Tehran team. The capital side, however, can draw inspiration from their all-conquering performance in this year's Hazfi Cup. Having played out two 1-1 draws in the past season, the two sides are desperate to go one better this time around as they aim to secure a quarter-final spot.

One of the four tournament first-timers to book passage to the second stage, Bani Yas have raised quite a few eyebrows through resolute defending combined with the scoring form of Senegalese Andre Senghor, sealing a qualifying spot at the expense of continental veterans Pakhtakor. The UAE hopefuls, however, will face a thorough examination by Al Hilal, who had a smooth group campaign with Morrocan striker Youssef El Arabi on target four times. The Saudi hosts welcome Bani Yas undoubtedly expectant of maintaining their undefeated run, but the visitors can look to the guile of their Argentine coach Gabriel Calderon, who guided Al Hilal to the Saudi title last season.

A 4-1 win over Al Nasr in Sunday's Saudi Arabian Champions Cup final is all that Al Ahli need as they travel to Abu Dhabi determined to topple Al Jazira. However, they must remain wary of the 2011 UAE league champions, who sent shockwaves across Asia as they sealed early qualification with two games to spare. Shouldering the hosts’ hopes is former Valencia and AC Milan striker Ricardo Oliveira, who has racked up an incredible 10 goals in only 6 games as Al Jazira have became the competition’s most prolific side. Al Ahli, for their part, can look to the form of Oman striker Amad Al Hosni, who scored 15 times as they finished runners-up in the Saudi League to Al Shabab.

Player to watch
With his ten goals already equaling the record set by compatriot Leandro in 2008, Al Jazira's Brazilian hot-shot Ricardo Oliveira will be aiming to both set a new Asian goalscoring benchmark and to steer his side through.

The stat
- The scoring chart of the Asian campaign has largely been dominated so far by imported players, with all the top-four scorers being from beyond the continent.

What they said
"Although our opponents Al Hilal are among the best clubs in Saudi Arabia and also Asia, we are lucky that our coach (Gabriel Calderon) was their former coach so we are not lacking at the tactic level. Having gone through to reach this stage, we will never look back," Bani Yas midfielder Amer Abdulrahman

AFC Champions League, Round of 16 fixtures
22 May
Al Jazira - Al Ahli
Sepahan - Esteghlal

23 May
Al Ittihad - Persepolis
Al Hilal - Bani Yas

29 May
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30 May
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