They say when it comes to love, age is nothing but a number.

But what about when it comes to the USC football team, which seems to have no qualms about starting an 18-year-old kid fresh out of high school?

Considering that many Trojan fans pay more attention to this team than their lovers, I guess the same rule applies.

Coach Pete Carroll announced Thursday that boy wonder Matt Barkley will start USC’s first game Sept. 5 against San Jose State, setting Barkley up to be the first true freshman quarterback to start a season opener at USC.

Talk about pressure.

But Carroll knows that if this love affair — er, quarterback situation — is going to work, Barkley can’t handle himself like a high school kid with jitters on prom night.

And fortunately for the Trojans, Barkley appears eons ahead of his time.

Since the day he set foot on the practice field, Barkley generated a buzz around Trojan football circles. Then after Carroll began to rave about him during spring practice, the hype grew to Coliseum-sized proportions.

Now, after Barkley was surprisingly tapped as the starter over third-year sophomore Aaron Corp, Barkley is basically all anyone wants to talk about.

Yet the kid with the golden arm said he doesn’t even allow those things to enter his mind.

When asked if he felt like people were watching his every move Saturday at USC’s final intrasquad scrimmage, Barkley was unfazed.

“I don’t think about that. I try to just picture that I’m at practice,” he said. “I try to block all that stuff out.”

To be clear, pressure in sports is not a phenomenon that athletes imagine. Pressure is real — it’s tangible, it’s heavy and it affects one guy more than any other on a football field: the quarterback.

So for Barkley to imply that he easily blocks the pressure out is of course a complete falsehood. But the fact that he’s saying he does shows he’s wise beyond his years.

Being a leader is often about how you handle yourself rather than the way you actually feel inside.

There is no question that Barkley is under the most intense pressure to perform. Every interception he throws will be scrutinized. Every bad read he makes will be attributed to his age. But if the way you handle yourself counts for anything, then Barkley, despite his inexperience, has my vote of confidence.

Carroll would not have made this choice if he weren’t 100 percent certain Barkley would give the Trojans a better chance to win games than Corp. That doesn’t mean Carroll isn’t wrong — only the games can decide that — but the way Barkley carries himself offsets his age.

That includes being honest about what he needs to improve on.

“[I need to] just get everything quicker, my reads and my footwork,” he said after the scrimmage.

He admitted that he was still over-thinking things on the field a little bit, “but for the most part, I am playing and just reacting to what the defense is giving me.”

Barkley clearly has the maturity and mental capability to play quarterback right now at USC. He has all the physical tools — a 6-foot-4 stature, an NFL arm and pocket presence. He has produced in game-like situations — 156 yards and one touchdown in this most recent scrimmage.

Barkley’s biggest challenge, then, will be to simmer down his gunslinger mentality.

Barkley can draw from the example of Mark Sanchez. What held Sanchez back early in his career with the Trojans was not that he wasn’t able to make throws and reads, but that he too often tried to squeeze the ball between multiple defenders or go for the home run every chance he got.

“That’s what really kept Sanchez down for a long time when he was a young guy coming up,” Carroll said. “He kept trying so hard to make something happen and he couldn’t catch John David [Booty] because of that.”

Obviously Barkley has been able to wrangle in his inner-Mark Sanchez enough to put himself in the starting position. But that doesn’t mean the process is finished.

“That’s what all quarterbacks have to fix, all quarterbacks have to stop trying so hard,” Carroll said. “That will continue to be an issue.”

Barkley showed warning signs of risk-taking in his high school days, when he threw 18 interceptions in his senior year at Mater Dei.

Saturday’s scrimmage also pointed to some growing pains Barkley will likely struggle with early on in his career at USC. On his very first play, his foot got caught up with one of the offensive linemen as the ball was snapped, causing him to stumble as he flicked the ball to running back Joe McKnight.

“Good start,” Barkley said smiling, when asked about what immediately came to his mind.

Later in the practice game, with the offense threatening near the goal line, Barkley scrambled to his right and chucked the ball toward the endzone where it was almost intercepted.

Barkley claimed he was trying to throw the pass away where no one could catch it, but it was dangerously close to being a turnover. He later responded by throwing a touchdown to sophomore tight end Blake Ayles and running for a score as well.

When Barkley takes the field Saturday, no one should expect a mistake-free outing. He will make throws he would like to have back, he will miss reads and he may even (heaven forbid) throw interceptions.

But if his overall performance translates into victories, he will have won over the hearts and minds of the Trojan faithful.

Within the team and on the USC campus, it seems the romance has already begun.

“Middle Ground” runs Mondays. To comment on this article, visit dailytrojan.com or email Josh at jjovanel@usc.edu.