1948 Providence Steam Rollers
If you are looking for the team with the least number of wins in a regular season, the Providence Steam Rollers did that in 1948 with a 6-win 42-loss record. They were among the pioneer teams of the league. However, they were so weak that this was the result they showed in their sophomore season. With things not going their way either in their third season, the team broke up after that.
