MASA playing rules for the 50 and Over and 60 and Over Slow Pitch Divisions are the same as ASA with the following exceptions, clarifications and emphasis:
THE LINE-UP
The defensive line-up may consist of eleven ( 11 ) players.
Rule 4, Section 1, Letter D, Number 1: Short Handed Player.
Exception: MASA Men's Senior Slow Pitch. If a team begins play with ten ( 10 ) or Eleven ( 11 ) players ( or a Senior's team with ten ( 10 ), eleven ( 11 ) or twelve ( 12 ), that team may continue a game with two ( 2 ) less players then it started with whenever a player leaves the game for any reason other than ejection, however, a team may not continue the game with less than nine ( 9 ) players.
BASE RUNNING RULE
1.	A base runner can over run second and third base without liability of being put out if he is not tagged with the ball before reaching the base. After over running a base, a runner must re-tag the base he over ran before advancing to the next base. Failure to re-tag as required would be considered an appeal play.
2.	A base runner advancing to home plate: All plays at home plate on an advancing runner are considered a force play.
HALF-INNING RULE
1.	From the first ( 1 ) inning through the fifth ( 5 ) inning, a half inning will be terminated when the offensive team has made three ( 3 ) outs or scored five ( 5 ) runs.
2.	For the sixth ( 6 ) and seventh ( 7 ) innings, a half inning will be terminated when the offensive team has made three ( 3 ) outs, there is no maximum number of runs to be scored.
EXCEPTION: If a team scores enough runs to apply the run ahead rule, twelve ( 12 ) runs, or if the team scores enough runs to win the game in the seventh ( 7 ) inning, the game shall be considered a complete game.
COURTESY RUNNER
1.	A courtesy runner, any player on the team, may be used once per inning.
2.	A courtesy runner may not be used for the batter, the batter must reach first base on his own.
3.	A courtesy runner may replace a runner at any base. A runner replaced by a courtesy runner may remain in the game as this move is not considered a substitution.
	NOTE: If a courtesy runner can not take his regular turn at bat because of being a base runner, an out will be recorded for his turn at bat.
DOUBLE FIRST BASE
A double base will be used at first base. The inside base ( White ) shall be for the use of the defensive player. Any use of the outside base ( Florescent Orange ) by the defensive player shall not be considered legal. The outside base shall be for the use of the batter base runner coming from home plate. Any incorrect use of the inside base by the batter runner will result in an out being called on the offensive player. The batter base runner coming from home plate may use the inside base only if a play is not imminent, i.e., an extra base hit to the outfield.
SCORING LINE RULE
1.	An eight ( 8 ) foot scoring line shall be extended from a point two ( 2 ) feet from the corner of home plate closest to third base into foul territory at a ninety ( 90 ) degree angle to the third base foul line. The end of the scoring line farthest from home plate shall be marked by a line of sufficient length to be clearly visible to a runner attempting to score and to the umpire.
2.	A foot down on or beyond the scoring line shall be the same as a foot down on home plate for the purpose of scoring a run. Running beyond the end of the scoring line shall be the same as not touching home plate ( SEE DRAWING ON PAGE THREE ).
3.	A runner that has passed the commitment line but has not reached the scoring line shall be declared out if a defensive player in possession of the ball touches home plate.
POINTS OF EMPHASIS
Rule 8, Section 9, Article K. Once a runner crosses a line twenty ( 20 ) feet from home plate, commitment line, he can not return to third base. Effect: The runner will be called out if he returns. The ball will remain alive.
HOME RUN RULE
Class AAA:
Home Run Limit: 3
Penalty in Excess: * OUT
Asterisk ( * ) indicates any home run in excess of the totals shown will result in the batter being ruled out