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Television money had also become much more important; the Football League received £6.3 million for a two-year agreement in 1986, but when that deal was renewed in 1988, the price rose to £44 million over four years. The 1988 negotiations were the first signs of a breakaway league; ten clubs threatened to leave and form a "super league", but were eventually persuaded to stay. As stadiums improved and match attendance and revenues rose, the country's top teams again considered leaving the Football League in order to capitalise on the growing influx of money being pumped into the sport.

When was the first year that clubs threatened to leave the Football League?
1988