Toews skated up to Thornton with about 4½ minutes left in the first period, jabbed him with his stick and then dropped his gloves. The star captains tangled up for a minute before Thornton dragged Toews to the ice and the referees skated in.
It was believed to be the first fight for Toews since December 2011, and the first skirmish for Thornton in about a year.
The Blackhawks led the Sharks 1-0 after one.
Copyright 2013 by The Associated Press
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