The Men's Singles champion at the 2012 Australian Open was Novak Djokovic.
There is no "2012 open tennis tournament".
Novak Djokovic won the men's singles at the Australian Open in 2012
There are countless professional tennis tournaments each year. There is no one extremely important tournament. The four grand slams (US Open, French Open, Wimbledon, and the Australian Open) are the biggest tournaments in tennis each year. in 2012 Novak Djokovic won the Australian Open and the three others have not been played yet.
This year, Roger Federer
The biggest titles of tennis are won in the Grand Slams: Wimbledon, US Open, French Open, and Australian Open.
Jim Courier defeated Stefan Edberg in the finals of the 1992 Australian Open