I was watching a HS game this past weekend. An attacker was on a breakaway. The keeper came out. Attacker touches the ball past the keeper and then the keeper trips the attacking player without ever touching the ball. The ref gives the keeper a yellow card and awards a free kick to the attacking team. The keeper was allowed to continue the game. I thought a yellow card in HS soccer meant the player has to leave the game for some period of time. Is there some special rule for keepers? Thanks!