Softball (safe or out ruling call)

Question
Hey Mark,
Runners on 2nd & 3rd, 2 outs bottom of 7th down by 3 runs, batter hits a single, both runs score and on trying to get in scoring position batter head for 2nd, the 2nd baseman is blocking the bag and as he catches the relay throw runner slides and knocks the fielder on top of him (2nd base got moved with the slide also). The fielder is holding the ball in his glove but never applied a tag on the ruuner.The ump ruled out on the play and we lost the game. What do you think?
                                    Thanks

Answer
Hi Romer,

I can only tell you of my impressions of this play because I didn't see it.

If B1 was attempting to advance to 2nd and F4 was blocking the base w/out the ball it is obstruction and we protect B1.  Simply "about to receive the ball" no longer applies in ASA.

If B1 touched 2nd and dislodged it before being tagged, the base is considered to have followed the runner, so B1 would be safe.

"The fielder is holding the ball in his glove but never applied a tag on the runner.The ump ruled out on the play"  I don't understand, we have to have a tag at some point for an out if B1 never reached the base and was not obstructed.  Why did the umpire call B1 out?  there's just not enough info for me to determine what happened.

Mark