While the man on the mark can advance to hurry his disposal, he is most vulnerable to being tackled from a player pursuing from behind.
When a player takes a free kick, the laws of the game stipulate that a protected area exists around the person in possession.
Additionally, there is an extra five metres of the protected zone behind the player on the mark; a prominent example of this specific infringement can be seen here.
[1] The laws of the game state that no player from either team is allowed within the protected area zone until the free kick is taken or play-on is called.
The protected zone has varied in size and shape over the history of the game, and was most recently adjusted in 2021 to prevent any lateral movement from the player on the mark.