THE AFL will broadcast ''No to homophobia'' advertisements on the big screen at tonight's Sydney-Collingwood preliminary final as part of a major push to stamp out discrimination.

Fans at tomorrow's twilight clash between Hawthorn and Adelaide will also see the clips.

The ads are a first for a national sporting code.

The move comes less than a fortnight after The Sunday Age revealed that openly gay Yarra Glen footballer Jason Ball had launched a campaign urging the AFL to show anti-homophobia ads during the grand final.