A Grand Slam is a tournament of the ranked players and it spans across different continents. There are 4 Grand Slams in a year. The ATP is the Association of Tennis Professionals.
Milos raonic of canada
Pat Rafter
Steroids are banned substances on the ATP and WTA tours. Players are subject to random testing.
ATP Tour Championship Tennis happened in 1994.
ATP Tour Championship Tennis was created in 1994.
Science Major: Association of Tennis Professionals
It is the Association of Tennis Professionals, responsible for the mens tour and world rankings of male tennis players.
ATP
Novak Djokovic is the top male tennis player on the ATP rankings.
Now known as the ATP World Tour, the association has been running since 1972, so that would make it 37 years.
Through WTA´s guidelines. The ITF tournaments first and then the WTA tournaments.