There came a situation in one game where there was a runner occupying first base (R1) and third base (R3), with one out. The batter then hits a ground ball to the left of the second baseman. He fields the ball and attacks R1, advancing to second base. R1 then stops and back pedals to first base to avoid the tag. The runner the second baseman then throws over to first base to get the battered runner out; with this, R3 advances home, and there is now a hot box between first and second because of R1.
After the runner is tagged at second, the umpire had tried to stop play claiming that because R1 did not just stop but back pedaled to avoid the tag, he is automatically out, and no run scores.
Was the umpire's decision right?