The Association of Tennis Professionals or ATP Tour was formed in 1972 to protect the interests of top professional players, but only began to wield significant power after wresting control of the game in 1988.

Leading players had become increasingly concerned with the lack of promotion and marketing within the game, and effectively staged a coup by which they persuaded directors of some of the world's top tournaments to lend their support.

In 1990 the Championship Series was introduced, designed to give extra importance to a number of high-profile events, which would evolve into the Tennis Masters Series and, in 2009, the ATP World Tour Masters 1000.

In addition, the ATP Tour took control of the end-of-season tournament known simply as the Masters, which was run by the International Tennis Federation almost as a showpiece event, but did not count towards any world-ranking points.

The tournament was renamed the Tennis Masters Cup and designed on a round-robin format to feature the best eight players in the world from that year.

Andre Agassi won the first Masters Cup with a four-set victory over Stefan Edberg. Pete Sampras and Ivan Lendl hold the record for the most title wins, each with five.

In 2009 ATP Tour officials made the unpopular decision to make the nine rebranded ATP 1000 Series tournaments mandatory, warning of severe sanctions on players who missed out without reason.

They also controversially dropped Monte Carlo and Hamburg as elite events, although Monte Carlo sued and was eventually restored on to the list.