"I am staying so I can finish what I started," then-Trojans quarterback Matt Barkley said to the cheers of students in USC's Heritage Hall in December of 2011.

Barkley had decided to forgo the 2012 NFL Draft and return to USC for his senior year. While Barkley already had fame as the face of the program, he forfeited a large amount of money with the decision. He figured to be a top-10 selection had he declared for the draft. While student-athletes are taken care of as far as housing and meals go, they don't receive a salary and can't sign endorsement deals. Their ability to earn an income is very limited. They work hard to showcase themselves so that NFL teams will take notice and make their post-collegiate playing years financially comfortable.

Barkley spoke with Matt Maiocco on "The 49ers Insider" – a podcast on NBC Sports Bay Area. He was asked about the impact of being such a high-profile athlete within a prestigious football program. "I don't know but I wish I could have gotten endorsement deals then, I'll tell you that," Barkley answered.

"I am not postponing my dream of playing in the NFL just so that I can have one more year of college life," Barkley said in 2011. "I am staying because I want to finish what I started."

USC was coming off of a two-year bowl ban handed down by the NCAA after the program was found guilty of a lack of institutional control. Barkley knew that he would be highly coveted had he left for the NFL. "I had confidence that I was going to go high," Barkley said on The Dan Patrick Show. "It wasn't really a question of that, as to why I came back."

The Trojans entered the 2012 season with the No. 1 ranking in preseason polls. After starting the season 6-1, USC went on to lose five of their last six games, including three straight losses to end the season. They finished 7-6, including an embarrassing loss in the Hyundai Sun Bowl. Barkley's once-high draft stock plummeted. He ended up being selected by the Philadelphia Eagles in the fourth round of the 2013 NFL Draft.

USC's football program ran a pro-style offense. That is a rarity these days as most quarterbacks entering the NFL have very little experience taking a snap under center or even working within a huddle. That was not the case for Barkley. The problem was the team that selected him was run by head coach Chip Kelly, who ran anything but a pro-style offense. While other quarterbacks have to transition to a pro-style offense, Barkley had to transition away from one.

"I kind of did it backwards, if you look at it that way," Barkley told Maiocco. "I do think playing for Chip in that offense was definitely a unique experience – to gain experience in that type of offense, running those plays, the zone read and all the different options he ran."

Some believed that Barkley could have been selected as high as the second overall selection in the 2012 draft. Robert Griffin III, who was selected with the number two pick by the Washington Redskins, signed a four-year, $21 million rookie contract. If not at the number two spot, Barkley likely would have been selected ahead of Ryan Tannehill, who went to the Miami Dolphins at eight overall. Tannehill ended up signing a four-year, $12.7 million deal.

How tough was the decision to remain at USC for his senior year? "It was tough," Barkley told Maiocco. "I had people pulling me in both directions and I looked at the pros and cons to both sides of the story, talked to a lot of people on both sides of the NFL and at USC, alumni, and different coaches in the league. After, given all that information, I just felt in my heart, I felt at peace coming back.

"The fact that we were off the Bowl ban and we had scholarships again, could compete coming off a great junior year, I didn't want to look back and regret what could have happened. Even the fact that we didn't win my senior year, I don't regret it one bit."

Barkley remains an ambassador for USC, continues participating in community outreach programs in the Los Angeles area, and will continue to do so while he is playing up north for the 49ers.

Following his two years with the Eagles, Barkley spent a season with the Arizona Cardinals and another with the Chicago Bears, where he was a teammate with another current 49ers quarterback – Brian Hoyer. Barkley's first career win as a starter came last season when he led the Bears to a 26-6 victory over the 49ers in stormy Chicago weather. He completed 11 of his 18 passes for 192 yards in that game.

You can listen to the entire "The 49ers Insider" podcast interview with Barkley here.