Boogie Ellis scored 17 of his 23 points in the second half and Southern California scored 11 of the game's final 13 points to beat Washington State 80-70 on Thursday in Los Angeles.
The Trojans (16-6, 8-3 Pac-12) withstood a stellar outing by Washington State forward Mouhamed Gueye, who recorded his third straight double-double with a career-high 31 points and 12 rebounds. Justin Powell added 11 points for the Cougars and Andrej Jakimovski had nine.
Drew Peterson scored 20 points and Tre White added 14 for USC, which has won 11 straight home games since dropping its season opener to Florida Gulf Coast.
Washington State (10-14, 5-8) shot 45.8 percent from the field and 8 of 23 (34.8 percent) from the long distance. The Cougars have lost four of their last five following a three-game winning streak.
USC won its third straight and avenged an 81-71 loss to Washington State on New Year's Day. The Trojans shot 51.9 percent from the field and 47.4 percent (9-for-19) from 3-point range.
The Trojans led by seven before Washington State responded with an 11-2 run to move ahead 65-63 with 4:29 remaining.
USC scored the next five points and held a 71-68 advantage after Ellis made two foul shots with 1:50 left. Peterson made one of his three 3-pointers to push the lead to six before Vincent Iwuchukwu's dunk sealed the victory.
The Trojans struggled from the start to contain Gueye, who scored Washington State's first 11 points and 13 of the Cougars' first 15. USC center Joshua Morgan exited with a right ankle injury early in the game and did not return.
Washington State stretched its lead to 13 points midway through the first half before Peterson's 3-pointer capped a 17-2 run and put USC ahead 30-28.
Gueye scored 20 points in the first half for the Cougars, who trailed 37-35 at the half despite outrebounding USC by a 20-10 margin.
Washington State guard Jabe Mullins (two points) started in place of DJ Rodman, who sat out with an illness.
--Field Level Media