Defensive play rule

Question
I have a question regarding use of feet to stop a ground ball. I was recently playing left field and a ball was lined down the left field line. I couldn't get over to cut it off so in an attempt to stop the ball I stepped on it. Because the batter/baserunner had assumed the ball got by me the attempted to run to 3rd base, but since I had in effect stopped it, I easily threw it to 3rd and the runner was forced into a tag-out. The opposing team said it was illegal for me to use my feet to stop the ball, claiming defensive interference. The umpire said the play stood as called without much explanation. I would just like to clarify that he made the correct call. And of course there is a friendly wager on the line with the other team. Thanks in advance for any help.

Answer
Hi Chris,

Tell them to pay up, there is no "thou shall not stop the batted ball with your foot" rule anywhere.

The umpire was absolutely correct!

Mark

ps there is no such animal as "defensive interference"  tell them they owe double for not knowing proper softball terminology.