USGA expresses regret over rules controversy at US Open

"While our focus on getting the ruling correct was appropriate, we created uncertainty about where players stood on the leader board."

The United States Golf Association has expressed its regret over the rules controversy that threatened to overshadow Dustin Johnson's victory at the US Open.

The American carded a closing 69 at Oakmont to finish four under par, but only after being given a one-shot penalty following an incident which left players, officials and spectators unsure of his score with just seven holes to play.