The Grand Lake Mariners enters its 30th season in 2021. Grand Lake is the second oldest member of the Great Lakes Summer Collegiate Baseball League (GLSCL). The Great Lakes league is one of eight (8) summer leagues approved by the National Alliance of College Summer Baseball (NACSB) and the only summer collegiate league sponsored by major league baseball which also requires the use of wood bats.
All players in summer collegiate baseball teams under NACSB sanctions are members of college teams and have completed their freshman year and have at least one year of college eligibility remaining in addition to meeting all eligibility requirements of the NACSB which are NCAA based.
The 2021 Great Lakes Summer Collegiate League consists of fourteen teams in Ohio, Michigan, and Indiana.
The Mariners are the second oldest team in the league – starting in the 1990 season. A baseball fanatic named Dave wanted to see a team in his native town of Celina, Ohio, and wrote a letter to the GLSCL. Lou Laslo was the commissioner at the time, and after visiting Celina, he later approved the franchise. The Grand Lake Mariners team name is based on being on the shores of Grand Lake St. Mary’s. The GLSCL at the time was just three years old and had seven other members. The only one of those teams that are still active to this day is the Lima Locos. The Mariners have won three league titles – in 1994, 1997, and 2006. Recently in 2017, they were the runners-up. They play at Montgomery Field in Celina.