Stewart led a strong night for USC’s bench, which outscored Long Beach’s reserves, 23-3.
Dewayne Dedmon had eight points and 10 rebounds for the Trojans, who recorded only their third 2-0 start in the past 11 years.
Mike Caffey led the 49ers (1-1) with 17 points and James Ennis added 13. Long Beach State shot only 29 percent and had 18 turnovers.
USC went on a 23-4 run after Long Beach State tied it at 35 early in the second half. Dedmon capped the run with a tip-in of Terrell’s miss, then dunked an alley-oop pass from Byron Wesley for a 58-39 lead.