Force play or tag play
 

Situation the other day in Arizona high school baseball...

2 outs, bases loaded. Ground ball to the third baseman. The third baseman opts to tag the runner instead of touching the base. The runner stops in his tracks and turns to run back to second, not knowing there was a runner on first. He was eventually tagged out after the runner crossed the plate...

My question is... Did the third baseman forefit the force play at third base by tagging the runner, allowing it to be ruled as a tag play and the run allowed to score?

Nope - same as force play. Tag makes no difference here as R2 is forced to 3B.

What is a force play? A play on a runner who is forced to advance by the batter becoming a runner. Was R2 forced to advance in the OP? Doesn't matter how he was put out if the out was made before he reached his advance base.

The only way there would not be a force play any longer is if there were 1 out or less and the tagging of a runner (for example the runner from second), then the force would be off for the runner that was on 3rd. The runner at 3rd would have the option to either stay at 3rd base or go to the next base. The batter/runner and runner from 1st would still be forced to run to the next base. In your case there is a force play on everyone with the fact the bases are loaded. Tagging or touching the base is not at issue or change the status of the runners in any way.

Peace