Jason Day has withdrawn from the British Open, choosing instead to stay home with his newborn son.

The decision was not surprising for Day, a 24-year-old Australian who has said family is his top priority. His agent said Day's wife, Ellie, gave birth to Dash James Day at 10:15 p.m. Tuesday. It was the couple's first child.

Day is No. 21 in the world. A year ago, he was runner-up at the Masters and U.S. Open.

He would not be replaced at the British Open, which starts July 19, until the field is assured to go below 156 players. Day's decision Wednesday leaves 155 players, with two spots available this weekend. Webb Simpson, whose wife is expecting their second child and is not likely to play, has not officially withdrawn.