Gridiron Football Momentum

Question

We have this scenarios:

1. Kick off, after 45y, grounds near end zone, the kicking team dives on it and what if the kicking team player has the momentum that carries him into endzone is touchdown or touchback?
2. Muffed scrimmage kick, field goal attempt or punt, grounds near end zone the kicking team dives on it and what if the kicking team player has the momentum that carries him into endzone, is touchdown or touchback?

Answer 1

Assuming NFL rules here:

For situation 1, see Rule 6 (Free Kicks), Section 1, Article 4 (d) (1).

(d) The ball is dead if:

(1) it is caught or recovered by a player of the kicking team. If the catch or recovery is legal, the ball belongs to the kicking team at the dead ball spot.

Assuming the kicking team actually gains possession in the field of play, the ball is dead. Kicking team will have the ball at the point of possession. No touchdown or touchback.

For the other situation, by mentioning a muffed kick I assume you mean the receiving team has touched the ball. Then see Rule 9 (Scrimmage Kicks), Section 3, Article 2 and this is basically the same as the previous situation.

ARTICLE 2. KICKERS CATCH OR RECOVER BEYOND LINE. When the kickers catch or recover a kick beyond the line of scrimmage, the ball is dead at the spot of recovery, even if a member of the receiving team has first touched the ball.

Assuming possession is inbounds, then no touchdown or touchback.