The stadium was built in 1965 as Turnpike Stadium, a minor league ballpark seating 10,000 people named for the nearby Dallas–Fort Worth Turnpike (now part of Interstate 30, and known as the Tom Landry Highway). The Fort Worth Cats of the Texas League moved there as the Dallas-Fort Worth Spurs, and played there for the next seven years, setting many Texas League attendance records, especially after it expanded to 20,500 seats in 1970.
However, the stadium's real purpose was to attract a major league team to the Metroplex. It had been built to major league specifications, and was designed to be expandable to up to 50,000 seats. Due to its location in a natural bowl, only minimal excavations (such as connecting dugouts directly to the clubhouses) would be necessary to ready it for a big-league team. Although it was built primarily for baseball, its general shape was very similar to the major league multi-purpose stadiums that were beginning to emerge in the mid-1960s. The Metroplex had been mentioned as a possible expansion site since the 1950s, and Arlington Mayor Tom Vandergriff figured that Arlington, halfway between the two cities, would be the best site for a prospective major league team.