(Officialsportsbetting.com) – World number one Dustin Johnson is playing the “best golf in the world” and will start as the favorite to win the Masters next month, Jordan Spieth has said ahead of Thursday’s Houston Open. Spieth, who has a victory and two runner-up finishes at Augusta in the last three years, said he would have to be on top form to defeat Johnson at the first major of year, which starts on April 6. “I think Dustin Johnson is the guy to beat in golf no matter where you are,” Spieth said at a news conference on Wednesday.