The Trenton Thunder, a minor league affiliate of the New York Yankees, have announced their bat-fetching dog, Derby, has died of cancer.
"Derby was one of the biggest parts of our identity in the nine years of his life and it breaks my heart to share this news with our fans ahead of our 25th season," Thunder general manager Jeff Hurley said in a statement.
The nearly 10-year-old golden retriever began gathering bats for the Thunder as a 2-year-old in 2010. Derby was the son of Chase, the Double-A affiliate's first professional fetcher. Chase also died of cancer, in 2013 at the age of 13.
Like Chase, Derby became a part of the Thunder's fabric, even serving double duty as a water carrier by bringing beverages to umpires on hot days.
"His presence at our games and in the community was massive and every person and dog that interacted with him will miss him dearly," Hurley said.
Derby was a part of community outreach and was even immortalized with a bobblehead featuring him and Hall of Famer Reggie Jackson.
Derby is survived by his son Rookie and daughter Mickie, both born in 2013. Rookie joined the family business in 2014 and became the Thunder's full-time bat dog in 2016.
The Thunder announced they will host Derby Day on Jan. 26 -- Derby's birthday -- to celebrate the dog's life.