In keeping with the spirit of the original Diamond State Base Ball Club, the modern club plays most of its home games according to 1864 rules and uses reproduction equipment and uniforms replicating the original club.

The rules used for most Diamond State games were adopted by the National Association of Base-Ball Players at their convention of December 9, 1863.  Diamond State also occasionally plays by the rules of later periods.

Here are some of the ways in which 1864 rules and style of play differ from modern baseball:

  • Fielders do not use gloves.
  • The baseball has different stitching and is slightly larger (9 1/2″ circumference.)
  • Wooden bats tend to be longer, heavier and fatter at the handle.
  • The bases at first, second and third are made of canvas and are smaller (12″ square.)
  • Home plate is a flat, circular metal disc painted white.
  • Foul lines are marked from the middle of home plate only down as far as first and third bases (90 ft.)  Flags are placed further down each foul line, 100 ft. from first and third bases.
  • No base coaches are permitted within the playing area.  Players and captains may offer their teammates advice and direction from the bench at any time.
  • The first team to strike (bat) is determined by a bat toss or coin flip.
  • The pitcher stands in a designated area (not upon a mound) approximately 45 ft. from home base and tosses the ball with an underhanded delivery to the striker (i.e.- the batter.)
  • The striker (batter) must stand on a line drawn through the center of home plate and extending 3 feet to either side of the plate.
  • If the pitcher fails to deliver hittable pitches to the striker, the umpire may warn the pitcher and then call balls on subsequent pitches deemed to be unhittable.
  • If the striker (batter) does not attempt to hit good pitches, the umpire may warn the striker and then call strikes on subsequent good pitches.
  • After the umpire calls a third ball, the striker and all runners advance, even if not forced from a base.
  • Foul balls do not count as strikes.
  • The striker is out after accumulating three strikes during a turn at bat.
  • Foul tips caught either in the air or on the first bound by the catcher are considered outs.
  • Though not prohibited by rule, bunting is generally considered unacceptable.
  • In order to be considered an out, fair balls must be caught on the fly or on a single bound.  Runners cannot advance on foul balls.
  • The first striker of an inning is the player who follows the runner/striker who made the last out of the previous inning.
  • On foul balls, the ball must be returned to the pitcher, and then outs can be made by getting the ball to the base to which a runner is returning, before the runner arrives.  The pitcher need not wait for the foul return in the pitcher’s normal position.
  • A run cannot score on a caught foul ball, but a runner on third can advance after the ball has been returned to the pitcher.
  • A fair ball is a batted ball that first touches the ground, a player, or any object within fair territory (i.e.- inside the lines extending from home base through first and third bases.)
  • The batter runner may be tagged out if he overruns first, second or third base.
  • Only team the team captain may dispute an umpire’s call.