SANTA CLARA – Alex Smith was a terrible toddler, the type of child you wouldn't take to a restaurant, the type of kid you wouldn't dare bring on a plane.

Screaming jags, hissy fits – little Alex Smith was as willful, stubborn and headstrong as they come.

When he was 3 years old, he threw the mother of all tantrums, one so violent and long-lasting that his father, Doug, eventually took him into the shower and turned on the cold water to cool his son's scalding temper. Smith calmed down and didn't throw another.

Those stories are hard to believe if you've spent any time with Smith. He's as mild-mannered and polite as they come. More than one reporter has written that Smith is the type of guy you'd want your daughter to marry. (Spoiler alert: he's already married).

Indeed, Smith's amenable personality is one of the reasons the 49ers drafted him No. 1 overall in 2005.

Smith's previous coach, Mike Singletary, once called Smith "meek." A former NFL middle linebacker, Singletary could summon a fire-and-brimstone speech at the snap of a finger, and he couldn't understand why Smith, the supposed leader of the team, didn't display the same kind of emotion.

Singletary tried to bring it to the surface during his tenure, including a famously furious sideline rant during a game against the Philadelphia Eagles that was caught on camera. Mike Nolan, the coach Singletary replaced, had similar frustrations with Smith.

What Singletary and Nolan didn't understand was that the quarterback was every bit as bullheaded, dogged and fiery as they were. His, however, was a controlled burn.

How else to explain how Smith could endure one of the roughest stretches any quarterback has gone through and still want to stick it out in the city where his career began?

Smith's battle wounds – emotional and physical – are well-documented, but they're worth recounting as he gets set to finally enjoy his day in the sun.

He's had a different offensive coordinator every year he's been in the NFL, and he's had almost as many No. 1 wide receivers since 2005. He's separated both shoulders and has had two surgeries to his throwing shoulder. His lowest moments – a 2007 game in Seattle and last year's game against Philadelphia – were on national television.

Smith is like Tim Robbins' character in "The Shawshank Redemption" who knew that the combination of determination and patience were enough to overcome even the most dire situations. If someone should create a poster of Smith, pictured like prison escapee Andy Dufresne looking up to the heavens while a redemptive rain washes him clean, it wouldn't be a stretch.

Smith is a 27-year-old with old-fashioned sensibilities, especially in the world of professional sports. He's cerebral, he has a long attention span and puts responsibility ahead of all else. Those throwback qualities struck Jim Harbaugh when the coach first sat down with Smith one year ago.

Harbaugh said his first order of business was determining whether Smith wanted to return to the 49ers.

"Did he want be in the fire? Or did he want to wear the ball cap backward and back up somewhere?" Harbaugh said of the conversation.

"And I really felt that he had the competitive drive, the (desire) to prove himself, him wanting to do it here," he continued. "That's the thing that probably intrigued me the most. That character of wanting to come back and do it here in San Francisco, which is pretty rare, probably somewhere between rare and extinct. That's not just for football players. That's about anybody. … And I thought we could really work with that character. To me, that was special."

Smith also was wise enough to realize that he could succeed under Harbaugh.

When Singletary sat down with Smith, the conversation was about motivation or religion, and the quarterback felt he went into games underprepared.

Harbaugh and his assistants, by contrast, could fill his mind with all the football information it craved.

Offensive coordinator Greg Roman this week noted that Smith remains at the office late at night with the coaches and joked that "next year or in the future, he might be able to get home and get to bed a little earlier."

Late nights in the film room, however, are nothing new to Smith. It's what he had under college coach Urban Meyer at Utah. And after six painful NFL seasons, it's finally what he's getting with the 49ers. It's no coincidence that he's having the type of success he last had in college.

Alex Smith, the guy who crawled through a river of you-know-what and came out clean on the other side.

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