The first occupants of the Lloyd Street Grounds were the Milwaukee Brewers of the Western League, which opened the park in 1895 after leaving Athletic Park, the eventual Borchert Field. The Western League became the American League in 1900, but was still officially a minor league. In 1901 the American League became a major league, retaining Milwaukee as one of its charter members.
The first major league game played at Lloyd Street was on 3 May 1901 and the last on 12 September 1901. For 1902, the Brewers announced they were moving to St. Louis to become the St. Louis Browns, where they remained until 1954, when the Browns moved to Baltimore to become the Baltimore Orioles.
A new Western League formed in 1902, with the Milwaukee Creams as a charter member. This club played for two years in competition with the new Milwaukee Brewers of the newly formed American Association, which had re-opened the park eventually known as Borchert Field.
The city wasn't large enough to support two clubs, and the Western entry folded after 1903. The Western League continued on until 1937, maintaining a close relationship with the American Association, trading franchises back and forth on occasion, and playing post-season series from time to time. But 1903 was the end of the Western's Milwaukee experiment, and of the Lloyd Street ballpark as a professional venue.