The ownership group led by Nolan Ryan and Don Sanders began its operations in Round Rock in 2000 as the Dell Diamond opened, moving the Double-A Texas League's Jackson Generals to the new park, affiliating with the Houston Astros and setting attendance records for the Double-A level.

[15] In 2022, the Triple-A West became known as the Pacific Coast League, the name historically used by the regional circuit prior to the 2021 reorganization.

[16] Playing under a split-season format in 2023 in which the teams with the best league-wide records at the end of each half qualified for the playoffs,[17] Round Rock won the second-half title at 45–30.

[19] In a single round of playoffs to determine the PCL championship versus the Oklahoma City Dodgers, winners of the first half, the Express were defeated, two games to none.

Transactions → More rosters: MiLB • Pacific Coast League → Texas Rangers minor league players The "Play Ball" episode of The Simple Life, a reality television series starring young wealthy socialites Paris Hilton and Nicole Richie, took place during an Express game.

[51] The team made headlines in 2010 when it "signed" Billy Ray "Rojo" Johnson, described in a press release as an East Texan who grew up in Venezuela and had run-ins with the law.

In reality, Johnson was actor Will Ferrell, who briefly took the mound at Dell Diamond to promote his nearby charity golf tournament.