The son of immigrants from the Dominican Republic, Alex Rodriguez was born in New York City in 1975. His parents moved him and his two siblings, Joe and Susy, to the Dominican Republican when Alex was four, and then moved again to the Miami, Florida, area when he was eight. When Alex was in fifth grade, his father, Victor, a shoe salesman and a catcher in the Dominican pro baseball league, left the family, and his parents divorced. His mother, Lourdes Navarro, worked two jobs, as a secretary and a waitress, so that she could send Alex to private school. She and the three children lived in Kendall, Florida, a suburb of Miami.
Having learned baseball from his father, Rodriguez as a child idolized major league players Dale Murphy of the Atlanta Braves and Cal Ripken, Jr. of the Baltimore Orioles. At Westminster Christian High School in Miami, he was an honor roll student, devoutly religious, popular, and a sharp dresser—as well as an exceptional sports star, playing quarterback on the football team, point guard on the basketball team, and shortstop on the baseball team. In his junior year, Rodriguez batted .450 and his team won the national championship. He later credited coach Rich Hofman with teaching him to stop swinging at bad pitches. Rodriguez's baseball teammate Doug Mientkiewicz, who went out to play with the Minnesota Twins, told the Minneapolis Star-Tribune in 1999 that Rodriguez's greatness was already obvious in high school: "He would hit a ball hard enough to kill people." While Rodriguez was still a sophomore, scouts were projecting him as an eventual number one pick. As a senior, he hit .505 and stole 35 bases without being caught once.
The Seattle Mariners had the first pick in the amateur draft in June 1993, and they selected Rodriguez because he was the most exciting "five-tool" prospect in years: he could hit for average, hit for power, run fast, throw well, and play great defense. Agent Scott Boras, who represented many of the major league's top players, took charge of negotiations. It took more than two months to get a contract signed, a $1.3 million, three-year deal that included a stipulation that Rodriguez be called up to the major leagues no later than September 1994.
In 1994, Rodriguez played in 65 games at Class A Appleton, hitting .319, and 17 games at Class AA Jacksonville, batting .288. In mid-season, at the urging of Mariners manager Lou Piniella, he went directly to the major leagues. Still only 18 years old, he debuted on July 8, 1994, the youngest player in an American League starting lineup since Toronto's Brian Milner in 1978. Superstar Ken Griffey, Jr. insisted that Rodriguez be given a locker next to his, and from that time on Griffey both teased and advised Rodriguez. At 6 foot 3 and 195 pounds, the new kid was unusually big for a shortstop and exuded incredible confidence. "I know I'm ready," he revealed to Tom Verducci of Sports Illustrated. A right-handed batter, Rodriguez was hitless in three at-bats in his debut but had his first two major league hits the following day. Later that year Rodriguez was sent down to Class AAA Calgary. After the 1994 season, he played winter ball in the Dominican Republic and hit only .197, later describing it to Verducci as "the toughest experience of my life." Rodriguez returned for another call-up in 1995 after spending most of the year at Class AAA Tacoma. The Mariners knew he could play great defense, but he showed no signs of being a powerful hitter in his first two partial seasons, and when the Mariners played in two post-season series, Rodriguez stayed on the bench except for two at-bats.