Durant contributed 24 points, six rebounds and four assists while Westbrook donated 19 points, 10 helpers and eight boards as the top-seeded Thunder ran away with the opener of their Western Conference series.
Serge Ibaka (17 points, seven rebounds) and Kevin Martin (16, five boards) also reached double figures in the victory.
Former Oklahoma City standout James Harden scored 20 points for the Rockets, who were appearing in the post-season for the first time since 2010.
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