[1] On April 1, 2014, the Pittsburg Mettle were announced to play alongside San Rafael, Sonoma and Vallejo of the Pacific Association.

Former Major League Baseball pitcher Wayne Franklin, wife Cris, and business partner Tom Macari made up the Backwards K Group, the team's owners.

In 2015, the club rebranded after Khurram Shah, a local businessman, took over for the 2015 season during which the team made news signing former Oakland Athletics slugger Jose Canseco for two separate weekend stints.

[8][9] Pittsburg was managed by former Major League Baseball professional Aaron Miles, who was a part of the 2006 World Series champion St. Louis Cardinals.

[14] In 2018, Travis Blackley made the Diamonds first post-season start against the Sonoma Stompers where they were defeated 0–5 in the semi-final.