Harden hit 13-of-16 shots from the field, made four 3-pointers, collected seven rebounds and handed out 11 assists It was the 15th time this season Harden had scored at least 30 points.
The Rockets shot a sizzling 59 percent from the field and steadily built their lead until they took a 15-point advantage into the final period.
Portland was paced by 31 points and 11 rebounds from LaMarcus Aldridge. Portland has lost three of five.
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