how many players in the us open field
U.S. Open (golf) The U.S. Open is open to any professional, or to any amateur with an up-to-date men's USGA Handicap Index not exceeding 1.4.[3] Players (male or female)[3] may obtain a place by being fully exempt or by competing successfully in qualifying. The field is 156 players.
Home Run Derby (Major League Baseball) The field of players selected currently consists of four American League players and four National League players. The first Derby in 1985 featured five from each league, and the 1986 and 1987 events featured three and two players from each league, respectively. In 1996, the field was again expanded to ten players, five from each league (though in 1997, the AL had six contestants to the NL's four).