Johnson injures back falling down stairs on eve of Masters

Masters favorite Dustin Johnson took a serious fall on a staircase Wednesday and injured his lower back, and his manager said it was uncertain whether the world's No. 1 golfer would be able to play the tournament.It was a stunning development on an otherwise quiet day at Augusta National, where the course was shut down at 1:30 p.m. because of storms.The real calamity struck a few hours later.David Winkle, his manager at Hambric Sports, said Johnson fell on the stairs at the home he is renting in