Brashear also was suspended for an additional two games under a rule that allows the league commissioner to add additional games to a suspension if deemed necessary.
Following a face-off, Brashear landed several hard shots on Atlanta's Vitaly Vishnevski, who skated off the ice with several noticeable cuts.
In the final five minutes of regulation, several fights erupted, resulting in 162 penalty minutes in the final 62 seconds.
Because of league rules, Capitals' Coach Glen Hanlon was fined $30,000 and his Atlanta counterpart, Bob Hartley, was fined $10,000.
The salary recouped from the suspensions goes to the Players' Emergency Assistance Fund and the coaches' fines go to the NHL Foundation.
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