The current location of the ballpark, originally opened in 1959 or 1960, was named Manson Field in honor of the drive-in theatre owner to the south who allowed the use of the land. The Major field, built by dedicated fathers with shovels and wheelbarrows on weekends, was followed by the construction of the Minor field several years later.

Before moving to this location, games were played at Rosemont Park on a makeshift infield without an outfield fence. In the 1970s, the Major field was renamed Wilson Field and the Minor field became known as Dickinson Field. The Pee Wee teams were given Indian names such as Sioux and Apache, while Minor teams were named after birds like Blue Jays and Falcons. Only the Major teams were given Big League names. Tragically, floods devastated the fields in both 1989 and 1990.

In April 1994, E.M. Rosenthal and William E. Rosenthal made a significant donation to purchase the original 10 acres of land from the Manson heirs. This generous contribution played a pivotal role in securing the current site of the ballpark. The property where Melissa and Dry now stand was acquired later. When you visit the ballpark next time, take a moment to read the plaque on the concession stand that commemorates this donation and officially names the ULL complex Rosenthal Field.

By 1992, ULL had approximately 150 kids participating in six Major teams and six Minor teams. Fall baseball started in 1993, and softball began in 1994. The 1960 All-Star team included Jeff Newman, an eight-year MLB player who later became a coach or manager for several professional teams. Legend has it that Jeff, at nine years old, was hitting home runs on the Major field from both sides of the plate using a wooden bat.

In 2019 ULL had another significant flood that uprooted concrete poles, tore down outfield fences, and caused significant damage across the park. The rebuild would cost several hundred thousand dollars, but the families of ULL stepped up to fundraise and put ULL back on its feet. 2020 would bring another challenge with Covid, and while the league was still reeling from the flood, families once again kept the league afloat so that its rich tradition would continue.

In 2023, on the heels of the flood and challenges of Covid, ULL was once again prospering. Our 11U All-Star team advanced to Abilene to play for  a Texas West state title and returned home champions. 

As of 2024, we serve over 1,000 children per year with our softball and baseball programs.