Playoffs: 3 (1947, 1948, 1949)
The Muskegon Lassies joined the AAGPBL as an expansion team in 1946, representing Muskegon, MI. The Lassies went 46-66 their first year, good enough for sixth place in the 8-team league. The next season Muskegon saw a vast improvement, winning a close pennant race with a fine 69-43 record. Doris Sams was Player of the Year and the team had three of the top four in ERA with Sams (0.98), Amy Applegren (1.06) and Nancy Warren (1.13). Muskegon fell in the first round of the playoffs, dropping 3 of 4 games to the Racine Belles.
In 1948 the Lassies remained strong, going 67-58 for the second-best record in the eastern division. They again fell in the first round of the playoffs by a 3-1 margin. The next year the Lassies fell back to 6th place (46-66) despite another Player of the Year season from Sams. They took the first playoff round from the Kenosha Comets but were swept in the next round by the Grand Rapids Chicks.