obstruction or out

[Dakota]

Originally Posted by fiasco

...When the tag is applied, the runner believes they are out and stop their progress toward 2nd base. Thus the obstruction.

So, it is obstruction every time a runner believes they are out but are not?

I restate: it is not possible for a fielder in possession of the ball to commit obstruction. A fielder in possession of the ball may legally impede the runner; in fact, that is the fielder's job.