Former world No.1 blames weather delays for discomfort . He was 11 over par when forced out after two holes in San Diego . Tournament was his first PGA event of season after last week back surgery . Setback follows worst round of his professional career season .
Former world No.1 blames weather delays for discomfort . He was two over par when forced out after 11 holes in San Diego . Tournament was his second PGA event of season after 2014 back surgery . Setback follows worst round of his professional career last week .