fielder pushes runner off of the bag

[ggk]

did anyone see the phils- brewers last week. ryan howard was on 3rd base. a line drive was hit the the 3rd baseman who then dived towards third in an attempt to double off howard. howard dives back in, the ump signaled safe and then the 3rd baseman's glove(with the ball in it) hit howard's hand and pushed it off of the bag and then the ump ruled him out! the local paper rec'd an explanation from the ump which stated that there wasn't an intent to push his hand off of the bag, simply the 3rd baseman's momentum and therefore the play is legal and the runner is out. i heard this story second hand and couldnt believe it. how could they allow the runner to be pushed off of the bag - regardless of intent. why was the 3rd baseman even trying to tag howard?? all he had to do was touch the base - to which he was closer (howard slid head first the the outside part of the bag.
thoughts???