Asked if he thought the loss could cost him his job, Kiffin answered flatly, "No."
The Trojans struggled to contain Georgia Tech's triple-option attack. The Yellow Jackets (7-7) rushed for 294 yards on 63 carries while stopping a seven-bowl losing streak.
"I'm just glad we got the win," Washington said.
Tech's David Sims had 99 yards on 17 carries, but he got plenty of help. Zach Laskey added 60 yards on six carries, Vad Lee had 52 on 10 carries and Washington had 16 attempts for 46 yards for the No. 4 rushing team in the nation.
Sims also caught a 3-yard touchdown pass from Lee in the first quarter.
Lee and Washington combined to go just 5-for-10 passing, but two completions went for TDs passes and two more covered 26 and 49 yards, keying two of the team's scoring drives.
Tech used its two-quarterback attack masterfully, working them in and out of the lineup and playing to their strengths.
"I think both guys did some good things," Johnson said. "Vad hit some big plays and played well, and then in the second half we got kind of more geared into the run game and Tevin has a lot of experience and handled it really well."
High-powered USC finished with 10 first downs and eight punts as Georgia Tech shut down the Trojans' big-play threats all afternoon.
USC receiver Marqise Lee, who finished fourth in this year's Heisman voting, was held to six catches for 41 yards.
"To go out and perform the way we did today was a great feeling," said Yellow Jackets cornerback Rod Sweeting, who had an interception and was the game's MVP.
Wittek had four passes deflected at the line. His second interception came in the Tech end zone with 6:22 to go and the last came inside the Tech 10-yard line in the game's final minute. He was 14 for 37 for 107 yards.
"It was definitely our best game of the year (defensively)," said Johnson, whose team finished the regular season 6-7 after losing the ACC title game and needed an NCAA waiver to be eligible for bowl play.