In an interview on 710 ESPN Radio in Los Angeles, Wittek expressed confidence in his abilities -- and trust in head coach Lane Kiffin leading into the showdown against Notre Dame.
"If he wants to air it out, let's air it out," Wittek said of Kiffin. "If he wants to pound it on the ground, let's do that. I'm gonna go out there, I'm gonna play within myself, within the system, and we're gonna win this ballgame."
Smiling big in front of a pack of two dozen reporters after the Trojans' first practice of the week on Tuesday, Wittek also proclaimed himself ready to go and said he expects to have "a lot of fun" in his first collegiate start.
Of course, it happens to come against Notre Dame at the L.A. Memorial Coliseum.
"I've been ready all season for this to happen -- if it did," Wittek said. "Obviously the circumstances aren't the greatest with such a great quarterback being hurt, but I've been ready for this all year."
Kiffin said he thought Wittek "was awesome" in practice on Tuesday, starring in all sorts of drills and completing the vast majority of his passes.
Asked if the 6-foot-4, 245-pound Wittek knew the extent of the challenge he was facing with Notre Dame's dominant defense, Kiffin indicated he might not.
"I think sometimes what's good is to be so young that you don't know," Kiffin said. "I think he's just gonna go out and play."
Wittek, ESPN's 3rd-ranked quarterback in the class of 2011, is replacing the injured Matt Barkley, who suffered an AC sprain in his right shoulder in USC's 38-28 loss to UCLA on Saturday.
Barkley, a four-year starter for the Trojans, has been ruled out for Notre Dame but could still play in USC's bowl game next month. Wittek has been his primary backup all season, appearing in three games and completing 8-of-9 pass attempts for 95 yards and a touchdown.
Wittek also took over for Barkley in high school, at Santa Ana Mater Dei, where Barkley started from 2005-2008 and Wittek helmed the team in 2009 and 2010.
Both players enrolled early out of Mater Dei. Barkley won the Trojans' starting job immediately under former coach Pete Carroll, while Wittek redshirted his first year while behind fellow freshman Cody Kessler on the depth chart.
Barkley said Tuesday he expects Wittek to smoothly lead USC.
"Just talking to the other guys about his huddle presence, it sounds like he's got it," Barkley said. "We'll see what it's like when he gets into the Coliseum for the first time, but I have no doubt.
"He's played in big games before, and he's a tough kid. I think he's gonna have a great performance."
Barkley also said Wittek has the necessary tools to excel against the Irish.
"He's got a gun," Barkley said. "I think he will let it rip."
Barkley showed up to USC's Tuesday practice halfway through the session, with a sling supporting his shoulder. Afterward, he said he was dealing with the disappointment of his collegiate career potentially being over.
"To not be able to suit up and be with my guys, it's gonna suck," Barkley said. "But I don't think one game will define my time at USC. It's been a tremendous journey."
Barkley led the Trojans to two wins over Notre Dame on the road but never got the chance to host the Irish at the Coliseum. He sat out of the November 2010 game because of a sprained ankle, and Mitch Mustain started the Trojans' 20-16 loss.
It's possible Barkley could still play in the Trojans' bowl game this season, depending on the bowl and his recovery process.
AC sprains typically require 2-8 weeks of rehab. USC could play its bowl game as early as Dec. 22, which would be five weeks from the day of the injury, and as late as Dec. 31, just over six weeks from the UCLA game.