The slow-paced victory was Utah's second in a row after the Jazz had lost three straight. Phoenix has lost seven of its last eight outings.
Jefferson scored 21 points and grabbed eight rebounds. Utah led by as many as 15 points midway through the final period.
Marcin Gortat paced the Suns with 18 points and 11 boards. The Phoenix effort was hampered by 20 turnovers. Only 20 foul shots were attempted in the contest.
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