Entities:

1. Team

   • Attributes: Team_ID (Primary Key), Name, City, Coach, Captain

2. Player

   • Attributes: Player_ID (Primary Key), Name, Position, Skill Level
   • Relationships: Belongs to Team (many-to-one with Team), Is Captain of Team (one-to-one with Team)

3. InjuryRecord

   • Attributes: InjuryRecord_ID (Primary Key), Details (or other relevant attributes)
   • Relationships: Belongs to Player (many-to-one with Player)

4. Game

   • Attributes: Game_ID (Primary Key), Date, Score
   • Relationships: Host Team (many-to-one with Team), Guest Team (many-to-one with Team)

Relationships:

1. Belongs to Team (between Player and Team)

   • Cardinality: Many players belong to one team (many-to-one)
   • Role Indicator: "Belongs to" (or something similar)

2. Is Captain of Team (between Player and Team)

   • Cardinality: One player is the captain of one team (one-to-one)
   • Role Indicator: "Is Captain of"

3. Belongs to Player (between InjuryRecord and Player)

   • Cardinality: Many injury records belong to one player (many-to-one)
   • Role Indicator: "Belongs to"

4. Host Team and Guest Team (between Game, Team)

   • Cardinality: One team can be the host in many games, and one team can be the guest in many games (many-to-many)
   • Role Indicators: "Host Team" and "Guest Team"

Assumptions:

• Each team has only one coach.
• Each game involves exactly two teams (host and guest).
• The skill level of a player is a numeric value representing their skill in the game.
• Injury records are associated with a specific player and are not shared among players.
• There is no explicit representation of players' individual statistics or game statistics in the given requirements.