WCT Finals and Masters
I think the post about these two tournaments is apt. THere is a number of times in the 1970's I have seen the WCT finals tournament mentioned as a major. Players certainly viewed it as such at the time. This continued into the early 80's. It was a hotly contested tournament where the best of the best played. It had far fewer than 128 players (16 players). But that didn't detract at all from the achievement. Similarly the Masters - with 8 players. Players all wanted to win this. Discussions about who was number 1 for the year sometimes balanced on the outcome of this tournament.