SAN DIEGO (AP) -
Gaglianone's third field goal gave Wisconsin (10-3) its first win in seven tries against USC (8-6). The teams hadn't met since 1966, and two of USC's wins in the series were in the Rose Bowl, in 1953 and 1963.
Wisconsin's Sojourn Shelton intercepted Cody Kessler with 1:44 left. Kessler was hit from behind by Jack Cichy.
In the third quarter, Cichy sacked Kessler on three straight plays.
The Trojans got to the 50 in the final seconds before Kessler threw four straight incompletions.
USC, which beat Nebraska in last year's Holiday Bowl, had taken a 21-20 lead on Kessler's 7-yard touchdown pass to Darreus Rogers with 10:19 left.