INT or no call?

[SC Ump]

Mike,

This is really a "had to be there" situation, but as I'm visualizing it, F4 really CHOSE to slow up and did not even come close to R1, thus it would be hard for R1 to be ruled as interferring.

Unless your are 100% sure that the runner's actions interferred with the fielder, then I don't think you can call it.

You said yourself that, "there would have likely been a clear basis for interference (possibly a collision)". How do you know that R1 would not have changed her path or slowed up if F4 continued her charge?

I'm not implying that players involved in interfernce or obstruction have to go full speed into a collision before a call should be made, but as I'm seeing the play by your discription, I'm just not seeing interference.