But when the bullpen gate opens, it's a different story.
"Then he's a different person - I don't even know if he is a person!" CSUF assistant coach Jason Gill said.
His dual personalities jokingly earned Cordero the nickname of "The Chief" by former teammate Jon Smith, after the character in 1975's "One Flew over the Cuckoo's Nest."
Chief Bromden, played by Will Sampson, was a schizophrenic Native American who turned out to be silent but deadly - much like Cordero coming in for the final three outs.
CSUF Head Coach George Horton characterized Cordero's transition from calm and stoic on the bench to intense and nasty on the mound.
"He's a consummate team guy. Modest and unassuming, until you give him the ball and tell him to close out the ninth, " he said.
Horton said Cordero is humbly confident in the pressure cooker of protecting a late-inning lead.
"He doesn't do it with arrogance, but his personality changes," Horton said. "As a coach, you want that balance of mild-mannered off the field and competitive on the field."
Cordero acknowledges that he can get emotional when he is on the mound, but that he tries not show it.
"I keep it within myself. I try to stay as calm as I can out there, " he said.
Whatever he is doing is working.
Within a year of being drafted, the 25-year-old took over ninth-inning duties for the then-Montréal Expos in June of 2004 and hasn't looked back since.
The well-traveled Titan has finished games on major league stages everywhere from South Florida to French Canada, and back to the OC - Cordero put away the Angels on consecutive nights during a 2005 Interleague series in Anaheim.
Up the 57 Freeway at Goodwin Field, his 34 saves are still a CSUF record. During Cordero's 111 games as a Titan from 2001-2003, the team played in the College World Series two times.
Former Titan Danny Dorn, also drafted by the Reds this past June, said: "It was awesome playing alongside Cordero. Late in the game, he's lights out in the majors just like he was here."
Cordero likes to stay connected locally.
He still calls Southern California home in the off-season and said Heroes and the Slide Bar rank among his favorite local hotspots to frequent with his former Titan teammates.
A kinesiology major, Cordero said that Professor Michelle Barr was his favorite instructor at the university.
He added that one his off-field highlight from his CSUF days was attending the soccer games with his baseball teammates.
"We don't have a football team, so that was like our football," he said.
Horton praised the stopper for living up to his major league status both on and off the field.
Cordero has focused his attention towards positive causes both here and abroad, lending his time and efforts to hurricane relief, blood drives and visiting with wounded veterans at Washington D.C.'s Walter Reed Army Medical Center. He is also a regular supporter of his respective alma maters, Don Lugo High School and CSUF, locally.
"The stardom he's received hasn't changed his status," Horton said. "He still makes an effort to come out to the alumni games and make significant financial contributions to the program."
Cordero will soon be heading to Melbourne, Fla., for spring training to commence his fifth year of professional baseball. He will sign autographs, joke with teammates and talk to fans there much like he was doing at the alumni game here.
And that's because Chad Cordero is an all-around good guy - as long as he's not pitching.