...and weakest as opponents
[EDIT]
Hey Mike. Look my new method to play. Mike, I wait for your 100 goals.

It's possible.
Some possible scores:
Germany 23-0
Brazil 23-0
Holland 16-0
Argentina 16-0
England 1-0? (I didn't found good method for shot goals)
Italy 16-0
France 1-0? (I didn't found good method for shot goals)
Gods 1-0?
------------------
Total 97-0!
You can choose (with some luck) France or England as first opponent. Then you can shot more than 1-0 (I shot 6-0 with France but is possible more).
PS. Easiest to use is England. If you shot goal and opponent begin game then hold 'right' until your 3rd football player with no problem get ball and go ahead
[EDIT 2]
Possible scores:
Germany 24-0
Brazil 23-0 (possible 24-0 if shot first goal in 85 or 86 sec.)
Holland 18-0
Argentina 18-0
Italy 18-0
England 1-0? (I didn't found good method for shot goals)
France 1-0? (I didn't found good method for shot goals)
Gods 1-0?
------------------
Total 104-0!
If play with France or England as opponent possible is higher score. For example:
France 6-0?
Germany 24-0
Brazil 23-0
Holland 18-0
Argentina 18-0
Italy 18-0
England 1-0
France 1-0?
Gods 1-0?
-----------------------------
Total 109-0!
I think 110 goals is possible. If we find good methods for England and France then ...