I don't know the number of football tournaments, but here are some screenshots to help with your research:
"Social - Events" folders, some of the screenshots were taken during football matches:
Version 7.0 - 7.11
Version 6.0 - 6.9
Version 2.0 - 5.9
Rookgaard events (some of them football events with GMs) from all versions
Source (and more screenshots): Tibia Archive
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