USC had an easy time of it, with Arkansas falling behind, 38-27, at the half, and shooting just 36.8 percent for the game.
Taj Gibson had 18 points and eight rebounds; Gabe Pruitt had 11 points, five rebounds and four assists; and Daniel Hackett added eight points, six rebounds and five assists for the fifth-seeded Trojans (24-11), who face No. 4 seed Texas in the second round Sunday.
Patrick Beverley led Arkansas with 15 points and three rebounds. Sonny Weems had 13 points and four rebounds, while Charles Thomas scored 10 points for the 12th-seeded Razorbacks (21-14), who qualified for an NCAA berth by making it to the SEC Championship game last weekend.