Joshua Ballinger Lippincott Rosen (born February 10, 1997) is an American football quarterback for the Arizona Cardinals of the National Football League (NFL). He played college football for the UCLA Bruins and was drafted by the Cardinals in the first round of the 2018 NFL Draft. He was a top-rated recruit coming out of high school, where he was named a 2014 USA Today High School All-American. The first true freshman to ever start at quarterback for the Bruins in a season opener, he was named a Freshman All-American and was honored as the Pac-12 Conference Freshman Offensive Player of the Year in 2015. As a junior, Rosen was named second-team all-conference in the Pac-12 and broke the UCLA record for single-season yards passing. He is nicknamed "Chosen Rosen" and "the Chosen One".
Rosen was born in Manhattan Beach, California, to Charles Rosen, an orthopedic spine surgeon, and Liz Lippincott, a former journalist. Rosen's father is Jewish and was a nationally ranked ice skater who almost qualified for the Winter Olympics in the 1970s, and his mother is a Quaker who was the captain of the Princeton lacrosse team. Rosen had a bar mitzvah and identifies as Jewish, saying in 2016: "In retrospect, being Jewish is a big reason why I should have considered UCLA. Just because of how Jewish Hollywood is, and they really want someone to look up to because they just don't have professional athletes." He is the great-great-great grandson of Joseph Wharton, an industrialist and namesake of the Wharton School of Business at the University of Pennsylvania, and thus a descendant of Thomas Cornell, progenitor of the Cornell family. He is named after another ancestor, Joseph Ballinger Lippincott, who founded publishing house J. B. Lippincott & Co.