USC’s Dwight Lewis says he won’t cry . . . <i>during</i> the game

Senior day tradition dictates that Mom and Dad will cry, so pack extra tissues.

Chin up, chest out, dry eyes only.

“I’m not going to cry,” USC guard Dwight Lewis said. “It won’t hit me until after.”

That’s when Lewis will lose his cool, when the final buzzer sounds after USC’s game against Oregon State on Saturday.

That’s when he’ll join parents Rosa and the elder Dwight Lewis. They’ll cry, hold each other and smile. It won’t be the Lewis most people see, the laid-back player with the Southern drawl that rolls off his tongue like a smooth jazz tune from Bourbon Street.

This is Lewis’ first true senior day. High school didn’t really count: Hurricane Katrina forced him to transfer after his junior year from high school in Metairie, La., to Katy, Texas.

“I don’t remember much [of senior day],” he said. “They had some signs. All the players’ moms got flowers. That was it.”

Yet here, Lewis has played in more games (130) than any USC men’s basketball player before him and today will be his last at home.

“I feel like it’s flown by fast,” he said. “It was fun though.”

He made three trips to the NCAA tournament, reaching the Sweet 16 in 2006-07 when USC posted a school-record 25 wins.

His team won the Pacific 10 Conference tournament title last year, the school’s first.

Lewis was a part of only the fifth season sweep of cross-town rival UCLA since the 1940s, which happened this season.

But this season has been perhaps the most tumultuous for Lewis. The roster was gutted by early departures and recruits who didn’t show. Coach Tim Floyd departed amid allegations of scandal. Kevin O’Neill took his place, bringing with him a new system.

And then, in January, the program got rocked when the university announced self-imposed sanctions for allegations surrounding Lewis’ former teammate, O.J. Mayo. Among the sanctions was a postseason ban, meaning Lewis couldn’t fulfill his goal of playing in four NCAA tournaments.

“It was disappointing, but I’ve been over it for a while,” he said.

USC’s new goal became to win a Pac-10 regular-season title. After Thursday’s loss to Oregon, the chances of that happening are slim.

Lewis said he brought stability to this team.

Guard Marcus Simmons agrees. “Having a guy that stays and has been a leader, it’s big for us,” he said.

Lewis’ offensive game grew under Floyd. “He was a guy that couldn’t finish at the rim off a drive,” Floyd said.

Under O’Neill, it was defense, highlighted by Lewis’ recently holding Washington State’s Klay Thompson to a career-low two points on 0-for-12 shooting from the field. “He has helped himself by proving he’s a good defender, which is a lot more important to NBA people than these guys think,” O’Neill said.

His emotions almost never run high. They used to when he played AAU basketball in Louisiana, where he drew a lot of technical fouls for trash-talking.

“I had to mature,” Lewis said.

His game did. Emotions too.

They’re well-hidden now, tucked away. Cool is all you see. It seems a mix of both parents: Rosa, a lover of dance, and the elder Lewis, a jazz musician who actually played on Bourbon Street.

Yet even Lewis is not sure how they’ll be today.

“My mom’s a solid rock,” Lewis said. “She might shed one tear and that’s a wrap. My dad could go either way. But if he’s going to cry, he’s going to cry.”

Said the elder Lewis: “I’ll cry in a heartbeat. I have no shame in crying.”

When it’s over, his son might join him.

baxter.holmes@latimes.com