Those Fighters who choose to become Close Quarters Specialists learn to make use of advanced grappling techniques to better use their weapons in close combat and to control their opponents with powerful throws and grapples.

Also at 3rd level, you have advantage on any Strength check or saving throw that makes use of at least one free hand.

Beginning at 7th level, when you grapple a creature it takes 1d4 kinetic damage + your Strength modifier from your vise-like grip. Additionally, you have advantage on any weapon attacks against an opponent you have grappled.

Beginning at 10th level when you have a creature grappled, you can use one of your attack actions to attempt to throw them to the ground. Make a Strength (Athletics) check contested by the creature’s Strength (Athletics) or Dexterity (Acrobatics) check (the target chooses the ability to use). If you succeed you bring the creature to the ground while maintaining your hold on it, it is considered prone and grappled, while you remain standing, and you may make a weapon attack against it as part of this action. If the grappled creature succeeds, it is freed from your grapple.

Beginning at 15th level, you can attempt to further restrict the movements of a grappled creature. As an action on your turn, you can expend and roll a Superiority Die to attempt to restrain a grappled creature. The creature must beat your Maneuver Save DC with an Strength (Athletics) or Dexterity (Acrobatics) check (the creature chooses the ability to use) or take the die's roll as damage and become restrained until the start of your next turn. When you take this action, your movement speed becomes zero until the start of your next turn and you cannot use your reaction to attack.

Crowd Control

At 18th level you can attempt to throw a grappled creature as one of your attack actions. Make a Strength (Athletics) check contested by the creature’s Strength (Athletics) or Dexterity (Acrobatics) check (the creature chooses the ability to use). If you win the contest, the creature is thrown up to 5 + your Strength modifier feet and takes 1d4 kinetic damage + your Strength modifier and is knocked prone. The creature is thrown half as far and takes half as much damage if it succeed in the contest and is not knocked prone.

If the creature comes in contact with another creature (regardless of which of you won the contest), that creature must also make an Strength (Athletics) or Dexterity (Acrobatics) check (the creature chooses the ability to use) against your Maneuver Save DC or take 1d4 kinetic damage + your Strength modifier and be pushed back 2 + your Strength modifier feet and be knocked prone. The creature takes no damage and is moved only if it would occupy the same space as the thrown creature on a success.

If this second creature also comes in contact with another creature, it must also make the same saving throw against your Maneuver Save DC or take 1d4 kinetic damage + your strength modifier and be pushed back an amount equal to your strength modifier in feet and be knocked prone. The creature takes no damage and is moved only if it would occupy the same space as the creature that was shoved into it on a success.