Justin Irvin Upton is an American former professional baseball outfielder. Nicknamed "J-Up", he played in Major League Baseball (MLB) for the Arizona Diamondbacks, Atlanta Braves, San Diego Padres, Detroit Tigers, Los Angeles Angels, and Seattle Mariners. He was a teammate of his brother B. J. Upton with both the Braves and the Padres. While primarily a right fielder throughout his career, Upton later transitioned to left field with the Braves, Padres and Tigers.