[1] The Shinano Grandserows were one of the founding members of the Baseball Challenge League in 2007, participating in the inaugural season and finishing third out of four with a 31-35-6 record.

Shinano lost the three game Division Series 1–0,[2] whilst Niigata went on to the title that year.

The team would have its best season in 2017, finishing second place in the first half only one game back from the Toyoma GRN Thunderbirds, and topping the Advance-West with a 0.722 winning percentage.

In the Division playoff, they would sweep the Thunderbirds 2–0 in three games to reach the championship series, where they lifted the BC League Championship Trophy after a 4 -1 series win over the Gunma Diamond Pegasus.

[2] In 2014, Philippine international catcher Alfredo Olivares Jr. became the first Filipino player to play in the Japanese minor league system when he signed for the team, but only played for one season.