Ground game is football terminology that refers to running the game ball instead of passing it off. Essentially, it is describing the idea behind football, which is to run the ball and advance it as close to the goal as possible. Running the ball is fundamental when playing football, a team with a great running game is at an advantage come game time. A team that successfully runs the ball better than their competitors usually indicates that they're physically outcompeting the opposing team. Ground Game is impacted by defensive and offensive plays, as well as refereeing.
The best way to maintain possession for a decent amount of time is by running the ball, it puts the team that is ahead at an advantage for running out the clock. Running out the clock, with the ball in your possession is a classic tactic to hold onto control during a game. Running the ball also gives players the ability to get a first down quickly and efficiently should their ground game be up to par. Good ground game is incredibly necessary during a game, and gives teams a huge advantage.