KANSAS CITY, Mo. (AP) There was no rational reason to expect Alex Smith to be in his current position.
It was just a few years ago that he was a bust, a first-round pick of the 49ers who had failed to live up to expectations.
His job had been snatched away by Colin Kaepernick and he had been shuttled off to Kansas City for a couple of draft picks, his career scuffling along but just barely.
''He had a lot of adversity his first few years, had what, seven coordinators in seven years?'' Chiefs offensive tackle Mitch Schwartz said. ''He's had to bounce around a lot.''
All those hardships have only made these days more gratifying.
Now viewed as a consummate pro and the undisputed leader of the Chiefs, Smith is coming off perhaps his finest performance.
He set career highs with 34 completions on 48 attempts and threw for 363 yards and two touchdowns in a 33-27 overtime victory over San Diego in their season opener.
His leadership was never more evident than in leading the Chiefs to the biggest comeback in team history, a 24-3 second-half hole that was erased in the blink of an eye.
To cap it off, Smith called his own number on third-and-goal in overtime. It was an option and he kept the ball, slipping through a crease and into the end zone for the winning score.
''They went to review it,'' Smith said. ''Everybody was kind of going nuts and I was literally like, `I know they're reviewing it.' And I didn't want to start celebrating, then they come and take it back. Then when he finally said, `Touchdown,' after he reviewed it - yeah, I definitely lost it.''
Smith roared like a lion in celebration, a rare display of emotion from the stoic quarterback.
If his free-flinging style when the Chiefs needed him to throw didn't prove how comfortable he's become in Kansas City, it was that moment as he walked off the field.
And when he arrived to the locker room, the last player to make it after TV interviews, he was greeted by a roar from teammates.
The guy that got jettisoned from San Francisco has become the toast of the town.
''He's one of the most respected guys on the team,'' said Chiefs coach Andy Reid, who has loved him ever since his days in Philadelphia, and was a big proponent of the 2013 trade for him.
''You saw the love for him when he came in - that was obvious. They're happy for him,'' Reid said. ''Not only did he have a big day, he was able to score that last touchdown, which he called - that check he put in to win the game. I think everybody was happy for him that way.''
Smith no longer dwells on his divorce from the 49ers, any lingering animosity washed away by three straight winning seasons and the first playoff victory for Kansas City in more than two decades.
Yet consider this: Smith is 31-16 as a starter since the trade. Kaepernick is 22-18.
''He's a humble guy,'' Reid said, ''so everybody roots for him. They know what he's been through, kept his head high and took the high road with things during the tough times.''
Perhaps unfairly labeled a ''game manager'' or ''check-down Charlie,'' the numbers bear out just how productive he has been since his arrival:
- Thirty wins in his first three seasons are the best in franchise history, three more than Trent Green and seven more than Hall of Fame quarterback Len Dawson, who led them to their only Super Bowl.
- Through 47 regular-season games, Smith has completed 63.9 percent of his passes, making him the most accurate in franchise history. That list includes another Hall of Fame quarterback, Joe Montana.
- So far in his career, his quarterback rating - which considers attempts, completions, yards, touchdowns and interceptions - of 92.7 is better than any Kansas City quarterback.
''I think any time someone reaches a level that they haven't reached before that it proves to everybody - the whole room, including myself - that nothing's impossible,'' Reid said.
''Hard work, dedication and you can always better yourself, that's the way Alex approaches things, and guys see that. Not only does it help him in his game and his confidence, but it also helps the players around him.''
It's one of the big things that lured Schwartz over from Cleveland, where quarterback instability during his first four seasons continually scuttled rebuilding jobs.
''It really sets you back,'' he said. ''I played with some good guys there as well, but whether it was injuries or other circumstances it didn't quite work out. So that was a big thing that kind of brought me here was just knowing we had health and stability. It kind of solidifies everything.
''The quarterback is the cornerstone of the entire team,'' Schwartz said, ''so it's a big advantage.''
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