R3 with one out. The batter hits a hard grounder down the first base line behind the bag which is fielded cleanly by F3 who immediately comes up firing for home for a chance at cutting down the runner attempting to score from 3rd. The throw from F3 strikes the batter/runner who is digging hard up the line in fair territory outside the clearly marked running lane. R3 easily scores and the B/R continues to scamper down the line to 1st before anyone can recover the baseball. What have you got?
- The batter is out for running outside the lane and R3 is returned to 3rd base.
- The batter is out for running outside the lane and since he also interfered with the throw home, the interference is enforced on R3, who is also out. Inning over.
- The batter is safe and the run scores.
All we have here is a live ball and everyone is safe. The running lane is only enforceable on plays being made on the batter/runner at first base. He is not restricted to the lane when the play is being made at any other base–including home. The play stands. The batter and R3 are free to roam about the base paths.