Masters champion Bubba Watson has withdrawn from the Arnold Palmer Invitational.

Watson informed the PGA Tour on Wednesday that he was pulling out of Bay Hill because of the death of a childhood friend. No other details were immediately available. He is No. 2 in the world, leaving the tournament with four of the top five players in the world ranking.

Watson will try to become only the fourth player to defend his title at Augusta National. A year ago, he withdrew after an 83 in the opening round because of allergies. A few weeks later, he took out a membership at Bay Hill.

Watson was replaced by Kevin Kisner, who will play the opening two rounds with Brooks Koepka and Adam Scott.