What's The Call..Tuesday

Here is the situation: Runner at 1st, ground ball up the middle. F4 fields the ball in front of 2nd base, bobbles ball, drops ball, picks up the ball and never touches 2nd base. Runner from 1st slides into second and is safe. F4 ends up with ball between 2nd base and the mound.

For some unexplained reason the runner at 2nd leaves the base and takes a couple steps off the base toward 1st base. F6 yells to F4 to get his attention. F4 runs at the runner getting him in a rundown. F6 yells to F4 for the ball and touches 2nd base. Is the runner out, or does he need to be tagged because he acquired 2nd base safely and the force is no longer in effect? The runner did not give up, he was avoiding being put out by getting in the rundown.

Is there another force or does he have to be tagged?

Thanks for the great year guys. It was fun getting the chance to help with training you guys. You all did a great job. It was an honor. See you at the banquet. Enjoy the summer