The simple answer is “to keep the opposing team from scoring.”
There are a few instances in which you might do this, and there’s only one area in which it’s permitted.
You may sweep the opposing team’s stone when it crosses the far tee line, which bisects the house, or rings. (That would be the scoring end of the sheet of ice, not the delivery end.)
You can sweep that stone all the way through the house and past the back line and out of play. (Keep in mind that a stone touching the house – even by a millimeter – can score a point, and a stone sitting beyond the house but still in the field of play can be used as a “backstop” of sorts for another rock to score a point.)
Or you may sweep that stone just out of point contention.
Or you may sweep the stone roughly a stone’s width past the tee line in order to place your own stone right in front of it, called a “freeze,” which could allow you to score a point.
Here’s a video of a freeze shot on the button.
Thanks for the excellent question, Mary!
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You can watch games from the U.S. National Championships at the USA Curling website, courtesy of TESN – Twelfth End Sports Network. Ben “Tuck” Tucker is providing informative and entertaining commentary, and he’s had special guests join him. This morning, Olympian Ann Swisshelm stopped by to provide insight into the Carlson-George game.
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