From now on a player would be in an offside position if there were only two opponents between him and the goal, instead of three, as stated before.

It was sixty two years after the first football rules were set down (1863) and 21 years after the founding of FIFA (1904) that the International Football Association Board (IFAB) took a decision at its meeting on 13 June 1925 in Paris, following a proposal from the Scottish FA that had a major impact on the game and which changed things more than any other rule change before or since. Yet only a single word was altered and that was in the phrasing of the offside rule.

Under the old rule it had been pretty simple to catch an opponent offside and very difficult to outplay a defence, for example with a long through pass. Teams were practically forced to play sideways and try to penetrate a defence by dribbling through. The Board hoped that the alteration would take the advantage away from solidly defensive formations, and lead to more goals being scored. But the rule-makers proved to be rather naïve and underestimated the consequences. The change had the effect of forcing teams to strengthen their defences. Forwards suddenly had more room and new opportunities opened up before them.

The answer was a new playing system, but it took a few years to catch on. One of the most famous coaches of the era, Herbert Chapman, was the one who came up with the magic answer. With his plan, he and Arsenal in London achieved a series of successes in the late 20s and 30s which made the club world famous. His basic principle was: safety first.

Read the whole story here: http://www.draynehub.com/today-football-history-96-years-offside-rule-first-announced/