Don't know if you guys are familiar with this site (I sure wasn't), but the rankings actually look pretty decent for Asia (haven't checked the ranking for other continents): http://footballdatabase.com/ranking/asia
As related to Iranian teams (latest ranking as of March 1st) in the top 50:
8 - Sepehan
11 - Esteghlal
19 - Foolad
25 - Naft
34 - Tractor
36 - Perspolis
Ranking of countries by number of Top 20 teams by country
1 - Saudi Arabia: 4
2 - South Korea: 4
3 - Iran: 3
4 - Thailand: 3
5 - China: 2
6 - Uzbekistan: 2
7 - Qatar: 1
8 - UAE: 1
Japan: 0
As related to Iranian teams (latest ranking as of March 1st) in the top 50:
8 - Sepehan
11 - Esteghlal
19 - Foolad
25 - Naft
34 - Tractor
36 - Perspolis
Ranking of countries by number of Top 20 teams by country
1 - Saudi Arabia: 4
2 - South Korea: 4
3 - Iran: 3
4 - Thailand: 3
5 - China: 2
6 - Uzbekistan: 2
7 - Qatar: 1
8 - UAE: 1
Japan: 0
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