Who's ball and where will it be put into play?

[Wingmanbp]

A ball 1st and goal @B5. Pass intercepted by B6 in endzone trying to bring it out. Facemask by A21 in endzone, B6 runs out to A 20 where he fumbles and its recovered by A33. at the 21.
I am thinking there is no circumstance that I can see where A keeps the ball since they committed the foul after the first turnover. But im not sure if there is a rule that I am missing. My best guess is Team B's ball at the A 35 after facemask penalty enforcement.

[Kalle]

You should end up at A-10 after penalizing team A half the distance for the FM foul from the basic spot, which is the end of the related run, as it is by the team not in possession. 1/10 team B.

You are not missing anything. The only way team A would get the ball is if team B declines the penalty for the FM foul (I can think of only one scenario where that would happen, and even then team A would not really benefit from getting the ball back).

[DallasLJ]

You should end up at A-10 after penalizing team A half the distance for the FM foul from the basic spot, which is the end of the related run, as it is by the team not in possession. 1/10 team B.

You are not missing anything. The only way team A would get the ball is if team B declines the penalty for the FM foul (I can think of only one scenario where that would happen, and even then team A would not really benefit from getting the ball back).

  I think you misread the position of the ball.  Penalty happened in B's end zone, not A's.  So, yes, 15 yds from related run -- ends at 20, so plus 15 is B, 1st and 10 from the B35.

[Kalle]

  I think you misread the position of the ball.  Penalty happened in B's end zone, not A's.  So, yes, 15 yds from related run -- ends at 20, so plus 15 is B, 1st and 10 from the B35.

"B6 runs to A 20" - enforce from A-20 to A-10.

[Wingmanbp]

It should be B20. Long night again. Varsity game last night and didnt get home until 1130. lol He ran it out to 20 yards from the endzone lol