Standing on a fielders foot

Question
I have never seen this happen and couldn't find it in the rule book. On a catchers throw back to second on an attempted pickoff, the runner runs back to second and ends up standing on the fielders foot which is on the bag. This happens about the same time as the ball is arriving. The tag is applied and the runner called out. Is this correct? What about when a runner steps on the first basemen's foot if he has it over the bag while running past first. Would he be out also? If out:Is the force at first base good enough or would you need to tag him after he ran past first without actually touching it?

Answer
Usually when the runner steps on a fielder's foot the runners foot doesn't stay on top. Every situation that I have ever seen with a foot getting stepped on the runners foot rolls forward or back and touches the base. But if the runner gets tagged before his foot had a chance to roll then yes the runner would be out.

At the speed that the runner is moving to first again there is almost no chance that the bag wouldn't get touched. But in this situation if the bag doesn't get touched because of the first baseman's foot then obstruction would be called on the first baseman. Extra bases might be awarded if there was an over-throw at the umpire's discretion. Hope this helps!