Hasselbeck made a success of Pete Carroll's debut as head coach of Seattle (1-0) by going 18-of-23 through the air for 170 yards with one interception.
Carroll, who came to Seattle after nine years as coach at Southern California, entered the game with a 33-31 NFL career coaching record with the New York Jets (1994) and New England Patriots (1997-99).
Quarterback Alex Smith completed 26 of his 45 pass attempts for San Francisco (0-1), amassing 225 yards. Smith, however, tossed a pair of interceptions, one of which was returned for a touchdown by Marcus Trufant.
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