the last obstruction post ever(just kidding)

[Little Jimmy]

I was just reading the Paul L. post about obstruction on a possible steal. Responses were typically good. Two things have to happen, fielder without the ball blocking base or pathway and, and some phrase it, runner must show hesitation or deviation from approach. But what about this. Steal at second (or any advance really), fielder puts foot in front of bag awaiting the ball. Runner comes in, slides normally and does not deviate her path at all. Fielders foot prevents runner from reaching base. Then ball gets to fielder who applies the tag. No hesitation or deviation on the runner but impediment seems clear. Obstruction, right?