Mosquito Rules, Mosquito, 2014 (Oakville Minor Baseball Association)

This League is part of the 2014 season, which is not set as the current season.
PrintMosquito Rules

Rules and Regulations Mosquito 

Effective April 2009

Player eligibility for Mosquito is 10/11 years on Dec. 31st of current year 

Each player must have submitted a properly completed registration form accompanied by the registration fee prescribed by Baseball Oakville.


3.1 The Official rules of Baseball will apply except as amended herein

A) Each division convener in house league may establish regulations or guidelines as necessary for the proper management of the division, but any such regulations shall not contradict the official Rules and Regulations.

3.2 Field Dimensions

A) Mosquito -Base path 65ft. - Pitching mound 44ft.page1image9568

3.3 Regulation Games

A) Regular season games will be:
-Minimum 4 complete innings

-Maximum 6 complete innings

B) All playoff games will be 6 complete innings for Mosquito.

C) Games will be reduced by one inning if the home team is leading.

D) Incomplete games will be rescheduled as required by the division convener within 7 days. It is the Home teams responsibility to reschedule the games not played/completed within 7 days.

E) All games must start promptly at 6:15PM. A fifteen minute grace period will only be given if one or both teams fail to field the minimum of eight players at game time. No infield practice will be allowed 5 minutes before the scheduled start time. Abuse of this rule is to be reported to the league convener.

F) No new inning shall start after 8:15PM. Game is dead and ends at 8:25PM. If the game is ended at 8:15pm by the umpire and the inning is incomplete, the official score will revert to the last completed inning. Official time is determined by the head umpires clock.

G) In the event of an incomplete inning in ANY game, due to time restrictions, the score will revert back to the last completed inning. Regardless of any open inning status.

H) The winning team will report the score within 24 hours of the game to their divisions’ convener or designated representative.

3.4 Mosquito House League

A) No lead offs are allowed. In Mosquito, base runners may not leave the base until the pitched ball crosses the plate. Penalty. The runner is out and the ball is dead immediately when the runner leaves the base.

B) No base runner may steal home. He/she must be hit home. Or as a result of continuous over throws resulting from a batters at bat, he/she may continue home is errors permit.

C) The strike zone shall be from the top of the batter's shoulders to the top of his shins and four inches on either side of home plate.page2image19296

D) The batter may not attempt to advance to first base on a dropped third strike.

F) The infield fly rule does not apply.

 E) There is no bunting allowed.

3.5 Mercy Rule & Open Innings

If after the completion of 4 or more innings (3.5 if home team is leading) a differential of 10 or more runs exists, the plate umpire shall terminate the game at that point and the game will be an official game with the score as it was at the point of termination.

In addition to the above-after 4 runs have scored in any 1⁄2 ining, the 1⁄2 shall be terminated and the defensive team shall come to bat. The last inning (6th) shall be an Open Inning and the 4 run mercy rule does not apply.

If after 5 complete innings a team is winning by more than 10 runs the game is Mercied.

3.6 Batting Line-up

A) All players present at game time shall be listed on the team's batting line-up in the order desired by the Coach or Manager and bat in that order. Late arrivals shall be added to the bottom of this order. In the event a batter must be removed from the game during his time at bat, the last out in the order shall come to bat assuming the balls and strikes count of the replaced batter. If the batter becomes an out, he shall assume his regular turn at bat.

B) If a runner is removed by reason of injury or official ejection, the player last put out shall act as a pinch runner for the removed player.

C) Except for the above, there shall be no pinch runners or hitters allowed.

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3.7 Pitchers in House League

A) During the regular season and playoffs, a pitcher may pitch a maximum of 6 outs per game. These innings must be consecutive. Once a pitcher has been replaced by another pitcher, he CANNOT be brought back in to pitch in the same game.

Any pitcher removed during the course of an inning may not re-enter the game as a pitcher. For the purpose of this rule, an inning will be charged to a pitcher if he assumes the mound and throws at least one pitch to a batter. If extra innings are required, all players may pitch subject to the daily limitations.

3.8 Player Substitution

A) During regular season and playoff games, no player may sit out both the first and second innings of a game.

B) Each team member must play defensively two innings in an infield position per game, during regular season and playoffs.

C) No player may sit two (2) innings until each player has sat one (1). No player may sit three (3) innings until each player has sat two (2), etc.

C) All players in any regular season or playoff game must play defensively, no fewer than one inning less than the player who plays the most innings.

D) Players arriving late or leaving early, will be credited as being OFF for those innings, and the DEFENSIVE LINEUP must be adjusted accordingly. Or at the coaches discretion, for disciplinary reasons, may disallow the player from entering the game, after the start of the game.

E) Each team manager/coach must provide the opposing coach a lineup sheet, (Attached to back page of SCORE BOOK), indicating batting lineup and Player positions. Required off s for each player are indicated below.


Players Five Six Seven
10   5 off 0, 5 of f1 4 off 0, 6 off 1 7 off 1, 3 off 0

11   1 off 0, 10 off 1 10 off 1, 1 of f2 3 off 2, 8 off 1

12   9 off 1, 3 off 2 6 off 1, 6 off 2 9 off 2, 3 off 1

13   6 off 1, 7 off 2 2 off 1, 11 off 2 11 off 2, 2 off 3page4image18536page4image18856 page4image19016

14 3 off 1, 11 off 2 12 off 2, 2 off 3 7 off 2, 7 off 3

PENALTY: In the event of a violation of these rules, the game shall continue, however, the offending team will forfeit the game on any protest lodged, or upon further investigation by the League.

3.9 Ground Rules

Ground rules are to be established at the start of each game by the umpires - and may include, but are not limited to - the following as necessary:

A) In the absence of suitable fencing, lines extended from the home plate screen parallel to the first and third base lines will determine dead ball territory.

B) A pitched ball that becomes trapped in the backstop is immediately dead and runners may advance one (1) base. No runner may score.

C) A thrown ball trapped by a fence will be treated as an overthrow.

D) A battered ball that rolls or bounds under an outfield fence or into an outfield hazard will be a ground rule double.

E) A deliberate blocking of a base or a base runner deliberately running into a defensive player thus, causing a collision will result in either or both player(s) being ejected from the game. The purpose of this rule is to avoid injury to players.

4.1 Allowable members of a team
A) House league teams will consist of a maximum of 13 players.

B) Players may be drawn from other teams in the lower division when a team cannot field seven (7) players. The number of players in such instances shall be limited to 3 and must have the consent of the called up player's coach. No call ups will be allowed to miss their own division game to play as a call-up.

C) When more than nine (9) players are present at the game, including the called up players, the called up players shall play equal innings but shall not pitch, or catch and will bat at the bottom of the order.

D) Substitution of players from another team for any playoff game is not allowed.

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E) Violations of 4B, 4C, and 4D as determined by the Protest and Discipline Committee shall result in forfeiture of the game.


A) All players playing in House League shall be forbidden to assume the position of batter or base runner without wearing a CSA approved batting helmet with chinstraps. The chinstrap must be properly attached and worn under the chin. Deliberate removal of a helmet or strap while at bat or on base will result in an immediate out being called on the offending player by the umpire.

B) Metal spiked shoes may not be worn in any house league division. Rubber or plastic baseball shoes are optional.

C) Any person warming up a pitcher anywhere in the park shall wear a catcher’s mask and throat protector.

D) A catcher shall wear catcher's equipment provided or approved by Baseball Oakville (Rookie Ball and older) and shall consist of a helmet, mask, throat guard, chest protector, catchers glove and leg guards. A protective cup provided by the player must also be worn. This same item is also highly recommended for all other players.

E) Players must not wear any jewelry. Exception being Medic Alert jewellery and the coach & /or player must identify this to the Head umpire prior to he/she playing. Any players who is up to bat and is found wearing jewellery will be an automatic out.

F) Any person on the field who is cut during the game, or who arrives at the game with blood on their skin or clothing, will not be allowed in the dugouts, or on the playing field, until such time as proper first aid is given and the wound is covered or clothing is removed. Any equipment, including the baseball, must also be removed from the game should blood be on it (them).

G) Players must be in full Baseball Oakville supplied uniforms. Hat, jersey, pants and socks with their shirts tucked in at all times. NO player will be permitted to play in Shorts. NO exceptions and the umpires will enforce this rule. Continuing to enforce the NO short ruling should be encouraged at all practices too.


6.1 A player shall be ejected from the game - and may be suspended by the House League Vice-President or his designate - for one game for any of the following infractions substantiated as having been committed immediately before, during or immediately after any game.page6image23496

A) Using profane and/or obscene language.

B) Consuming any alcoholic beverages.

C) Smoking is view of any players while at the field is not recommended.

D) Use of illegal drugs.

E) Showing disrespect towards game officials, managers or coaches, players, parents or OMBA Executive personnel.

F) Destruction and/or abuse or theft or property belonging to the O.M.B.A., other players or spectators, or playing field facilities.

G) Unsportsmanlike conduct on or off the playing field including the throwing of bats, helmets or other equipment.

H) All players must be in OMBA provided uniforms.

6.2 The Protest and Discipline Committee may suspend a coach or manager for one game for any of the following reasons:

A) Infractions of 6.1A, 6.1B, 6.1C, 6.1D, 6.1E, 6.IF., 61G

B) Unsportsmanlike conduct particularly in the presence of players or spectators.

C) Missing three consecutive games without good reason and not insuring that a competent replacement is available to the team.

D) Not giving equal attention and consideration to every active player on his team.

6.3 Personnel ejected shall completely leave the vicinity of the ballpark and remain absent during any suspension period. In such case, the umpire will submit a full report to the Umpire in Chief, and if he or she deems further action, it shall be referred to the Protest and Discipline Committee.


7.1 Regular Season Games

A team may protest a game if an umpire's decision is claimed to be in violation of the rules.

A) If a protest is to be recognized, the protesting team shall immediately notify the senior game umpire of the nature of their protest who shall then notify the opposing manager that the game is being played under protest and witness a note of the protest on each game score sheet.

B) The protesting team shall file a written protest signed by the manager or coach with Protest and Discipline Committee not later than 24 hours after the conclusion of the game by e-mail or hand delivery.

C) A person or team official protested against may file a written reply with the Protest and Discipline Committee not later than 36 hours after the receipt of the copy of the protest.

D) In the case of an umpire's misinterpretation of the rules, the misinterpretation shall, if possible were rectified on the field. If not a protest may be filed as above.

E) A deposit of $50.00 - payable to Baseball Oakville - shall accompany all protests. This deposit is refundable.

F) If, in the opinion of the Protest and Discipline Committee, an appeal or protest is based on personal differences as opposed to compliance with O.M.B.A. rules, it will be rejected immediately.

G) The Protest and Discipline Committee will meet and attempt to hand down a decision not later than 24 hours before the next game of the affected teams or personnel involved.

H) At the discretion of the Umpires, they may also file a protest regarding player, coach, or manager’s performance.


1) Head to Head
2) Runs for and against differential
3) Coin toss

Each year, the O.M.B.A. shall appoint a Chairperson of the Protest and Discipline Committee. Should a protest be lodged, or a discipline is required, it shall become the responsibility of the Protest and Discipline Chairperson. The Chairperson shall convene a meeting of all affected parties - as soon as possible - and render a decision. The Convener of each division may only initiate this procedure.