SAN FRANCISCO -- Whichever body part he chooses as a weapon, his arm or legs, Colin Kaepernick will make a lot of teams look slow and overmatched. The 49ers' next opponents need to expect that, deal with it and not allow the quarterback to fluster them the way he baited the Packers into emotional quicksand during Sunday's season opener.

Technically speaking, Kaepernick took advantage of Green Bay's obsession with keeping him in the pocket and not being crushed under his heels for something akin to 181 yards rushing again. Playing in relative confinement, he ran for only 22 yards and beat the Pack with 412 passing, more than half of them in wicked cahoots with Ravens discard Anquan Boldin. 

Those numbers should be enough to explain the 49ers' 34-28 win, especially given the voraciousness of their defense. At least, Packers coach Mike McCarthy thought so. He dismissed the idea that back-to-back bits of foolishness in the first half had anything to do with the loss. 

First, he accepted an illegal-formation penalty that, if declined, would have given the 49ers a 4th-and-1 at the Packers' 5, guaranteeing a field-goal attempt. Instead, the 49ers had a 3rd-and-6 at the 10, another chance at the end zone and, if that didn't work, a chip shot for kicker Phil Dawson. 

Then, when the 3rd-and-6 play sent Kaepernick on a scramble out of bounds, theatrics took over, fulfilling a pregame story line and defiling sensible football. Clay Matthews, as promised/threatened, hurled himself at Kaepernick when the quarterback ran out of bounds at the 6, drawing a penalty. Joe Staley, the 49ers' left tackle, went after Matthews and drew an offsetting penalty that killed the 49ers' chances of a first down.

At this point, the idiocy should have netted out at zero difference in the game, leaving the 49ers with a 4thand-2 at the 6, pretty much where they would have been if McCarthy hadn't brain-farted on the formation penalty. But the syndrome had gone viral, infecting the officials, who somehow decided that offsetting dead-ball fouls negated the previous play. Again, the 49ers were granted an extra try on third down. This time, Kaepernick threw a 10-yard touchdown pass to Boldin for a 14-7 lead.

The officials later admitted to blowing the call on the offsetting penalties, and they bear primary responsibility for the error. But a sliver of poise from the Packers' coaching staff could have prompted a correction from the officiating crew. (The 49ers certainly wouldn't have said anything.) 

It's astonishing that so many football minds could be clustered together, and no one with a vested interest in the proper call noticed this error. The concept behind dead-ball penalties is not that complicated. But the wrong decision held.

"That's part of the game," McCarthy said, avoiding excuses and sounding gracious about the officiating mistake. But then he reacted badly to a question about the failure to decline the formation penalty: "So if that's your criticism, fine."

Really? A field-goal attempt becomes a touchdown in a game decided by 6 points, and that's not a factor? 

The 49ers seemed to have the Packers so thoroughly under control, so completely at the mercy of Kaepernick's arm, that McCarthy must have missed how close the game really was. Even as the Packers committed two turnovers to the 49ers' none and watched Kaepernick fry a secondary missing two regulars, this game stayed within a touchdown's reach all day. Aaron Rodgers was working his usual magic, racking up 333 yards passing. This game was absolutely decided by the smallest of plays and decisions.

Was the disorienting effect of Kaepernick's versatility responsible for the Packers' mental blips? No one can prove that, especially since the Green Bay offense made some silly errors as well.

"We had some guys who weren't as sharp as they needed to be today," McCarthy said (before he was asked about the formation decision). "I could point right to the second play of the game. Your primary receiver doesn't go out for a pass and another guy runs the wrong route and you take a sack."

But the fact is, the sight of Kaepernick running near the end zone lowered almost everyone's IQ but his. The hype about stopping him elevated egos over performance. Green Bay defenders seemed to be barking endlessly and pointlessly at Kaepernick.

"It was a hostile environment,'' Packers linebacker C.J. Wilson said. "We know what happened last (January), and there was a lot of emotion out there."

Stating the obvious, Matthews admitted that he screwed up. "I guess I should have figured he was going to step out of bounds, but it's nothing personal,'' he said. "I went up to him later and was joking around with him, but not a very smart play."

Staley admitted he screwed up, too, by retaliating. More to the point, he said his quarterback didn't begin to appreciate his teammate taking up his cause. "He yelled at me," Staley said with a big grin. "He's got more composure than his left tackle."

Kaepernick jumped off after the hit and didn't bother saying a word to Matthews. He calmly started signaling for a flag as he trotted away from the Packers' sideline. That attitude should have been infuriating to his opponents -- and worth imitating.