|League||Cape Cod Baseball League (Eastern Division)|
|Ballpark||Whitehouse Field at Harwich High School
75 Oak St, Harwich Center
|League championships||1983, 1987, 2008, 2011|
|Post-Season Division championships||1968, 1978, 1979, 1983, 1987, 1997, 2008, 2011|
|Regular Season Division championships||1968, 1987, 1997 (tie), 2016|
|2011 season||24-19-1, 49 points
2nd place, Eastern Division
|Management||Mary Henderson (President)
Ben Layton (General Manager)
|Manager||Steve Englert (Field Manager)|
The Harwich Mariners are a collegiate summer baseball team based in Harwich, Massachusetts. The team is a member of the Cape Cod Baseball League and plays in the league's Eastern Division. Harwich currently plays its home games at Whitehouse Field in the historic village of Harwich Center. Like other Cape League teams, the Mariners are funded through merchandise and concession sales, donations, and other fundraising efforts at games such as fifty-fifty raffles.
Harwich has only reached the championship series on four occasions in the past 27 years, but has won the title three of those times. In 2008, the Mariners made only their eleventh playoff appearance, just the second since their 1987 title. They won five of six to close the regular season with a record of 24-20, good for second in the Eastern Division. The Mariners swept through the postseason defeating East Champion Orleans 4-3 and 1-0 (18 inn.) and West Champion Cotuit 11-2 and 2-1.
The Mariners have been a member of the Cape League since 1930, when the team first began play in Harwich. In the league's Modern Era, the team has qualified for the playoffs on ten different occasions. Their first appearance came in 1968, when Harwich dropped the championship series three games to one to the Falmouth Commodores in what would become the first of Falmouth's four consecutive titles between 1968 and 1971.
Harwich would make the playoffs three times in the 1970s, reaching the championship series in 1978 and 1979, losing both times in four games to the Hyannis Mets.
Finally, in 1983, Harwich broke through, winning their first Cape League championship in the Modern Era. The Mariners finished the regular season with only the third best record in the league, but eliminated the Hyannis Mets two games to one to earn a berth in the championship series. Harwich prevailed over the top-seeded Cotuit Kettleers in five games, taking the series three games to two to win the crown.
Harwich wore the League crown again in 1987 after finishing the regular season with the best record in the league. The Mariners defeated the Yarmouth–Dennis Red Sox two games to one to win their second league title in five years. Y-D would respond two years later, winning the first of back-to-back CCBL titles in 1989. 1987, the year of Harwich's third championship, was also the last season that the League was not broken up into divisions.
In 2008, the Mariners finished the regular season second in the Eastern Division, but swept the first-seeded Orleans Cardinals (now Orleans Firebirds) in the Eastern Division Finals. In a rematch of the 1983 League Championship Series, the Mariners escaped with a two-game sweep of the Cotuit Kettleers, capped by a Mark Fleury walk-off single in game two which, in effect, ended the Mariners' 21-year title drought Harwich wore the League crown again in 2011, sweeping the Western Division's fourth-seeded Falmouth Commodores.
- Jason Bartlett 2000
- Dewon Brazelton 1999
- John Cerutti 1980
- Casey Close 1984-1985 (CCBL Hall-Of-Fame)
- John Flaherty 1987
- Jody Gerut 1996
- Mark Guthrie 1986
- Craig Hansen 2004
- Ian Happ 2014
- Scott Hemond 1986 (CCBL Hall-Of-Fame)
- Scott Kamieniecki 1984
- Tim Lincecum 2005
- Shaun Marcum 2002
- Adam Melhuse 1991
- Hal Morris 1985
- Dustin Ackley 2008
- Kevin Millar 1992
- Pat Pacillo 1982-83 (CCBL Hall-Of-Fame)
- Carlos Peña 1996
- Joe Saunders 2001
- Paul Sorrento 1985
- Cory Snyder 1983 (CCBL Hall-Of-Fame)
- Todd Stottlemyre 1985
- Josh Zeid