The voice, delicate and soulful, came from the front of the Arizona Wildcats' team bus.
Conan Amituanai's teammates could barely believe their ears.
"We were like, 'Whoa.' It was the biggest dude on the bus," quarterback Nick Foles said. "I couldn't believe it.
"He's got the voice of an angel."
Amituanai, the Wildcats' starting left guard, has been singing since childhood. But his ability to nail rhythm and blues songs has made the popular senior a locker room favorite.
Amituanai's renditions of SWV's "Weak" and H-Town's "Knockin' Da Boots," and songs by Boyz II Men, Bruno Mars and Jeremih keep his teammates constantly entertained.
His 6-foot-4-inch, 335-pound frame belies a voice that Amituanai's friends believe could make him a star.
Amituanai and UA student Zac Wiznitzer, a local rapper who goes by the name Zac White, released their first single - "See You Later" - last spring. Shortly afterward, Wiznitzer and Amituanai opened for Boston rapper Sam Adams at a Tucson club.
"Music has always been my thing," Amituanai said. "Sometimes, when I was a kid, I'd just play an instrument without singing anything. The music would just soothe me, calm me down, and I could go about my day from there."
Music and football have long been more than hobbies for the 22-year-old Amituanai, a native of Long Beach, Calif., who attended famed Poly High School. He signed with the UA in 2006 in part so he could play for his uncle, former defensive tackles coach Mike Tuiasosopo. He switched to guard during his redshirt freshman season and, after working his way to the top of the depth chart, cracked the Wildcats' starting lineup as a junior in 2009.
Wednesday's Alamo Bowl will mark Amituanai's 19th career start.
Among his teammates, Amituanai is known as much for his bellowing as his blocking.
The UA's offensive players were driving to Tucson from Fort Huachuca in 2008, when former Wildcat Mike Thomas commandeered the bus driver's microphone and began belting out an a cappella version of Jamie Foxx's "Wedding Vows." After a verse, Thomas - knowing Amituanai could sing - put the shy offensive lineman in the spotlight.
"Out of nowhere, he says, 'Conan, take over,' " Amituanai said. "I kept singing, but - you have to understand - I hate attention."
Teammate David Roberts, an aspiring music producer, soon introduced Amituanai to Wiznitzer. The lineman uses a Flip video camera to post songs on YouTube; with the help of senior defensive tackle Lolomana Mikaele, he's learning the guitar and ukulele.
"We all play it," Mikaele said.
Amituanai, who has a bachelor's degree in sociology, will move home next month to pursue his two passions. He'll prepare for the NFL draft and continue to sing, both at church and with his uncle, former USC standout Titus Tuiasosopo.
Amituanai's teammates are convinced he'll be famous - one way or another.
"He's definitely got a singing career ahead of him," Foles said, "Maybe 'American Idol.' "