SAN FRANCISCO — Ever since Coach Jim Harbaugh gave second-year quarterback Colin Kaepernick the starting nod over hot-handed Alex Smith, the question has hovered over the San Francisco 49ers like a cloud.
Did Harbaugh make the right decision?
The powerful and elusive Kaepernick offered a resounding answer Saturday night with a record-setting performance in a 45-31 victory over Green Bay in a divisional playoff game at Candlestick Park.
On a night when Kaepernick became Keepernick, the 49ers quarterback torched the Packers with his arm and his feet, rushing for two touchdowns and throwing for two.
He scored on runs of 20 and 56 yards. The 56-yarder was the longest run by a quarterback in the playoffs, surpassing a 51-yard run by Tennessee's Steve McNair in 2000.
"Guy's playing football, man, he's making it happen," 49ers receiver Michael Crabtree said of Kaepernick. "He's a playmaker."
Kaepernick also shattered Michael Vick's mark of 119 yards rushing — the previous postseason rushing record by a quarterback — with a game-high 181 yards in 16 carries, numbers slightly watered down by his two clock-killing kneel downs at game's end.
"The offense that we have creates a lot of confusion with the quarterback we have who can run as fast as he can," said tackle Joe Staley, part of an offense that gained 323 yards on the ground and 579 total. "He can also throw the ball downfield. We want to move the chains any way we can, but it's great to move the ball with the ground game."
Kaepernick got off to a bumpy start — his second pass was intercepted and run back 52 yards for a touchdown — but he never lost his composure, upstaging Packers quarterback Aaron Rodgers, the NFL's reigning most valuable player.
"Any time your teammates have confidence in you and they feel good about what you're doing, it makes you feel like you're doing the right things," Kaepernick said.
The Packers were outscored, 21-10, in the second half, and had two turnovers that led to 49ers touchdowns.
"It's pretty frustrating," said Rodgers, who threw for 257 yards with two touchdowns and an interception. "To go out and play like that is disappointing. We didn't do enough on offense to help our defense."
For the second consecutive season, San Francisco has advanced to the NFC championship game, where it will face the winner of Sunday's game between Seattle and Atlanta.
If the Falcons win, they will play host to the conference title game. If the Seahawks win, the game will be played at Candlestick.
Crabtree caught two touchdown passes for the 49ers, and Frank Gore and Anthony Dixon each ran for a score.
"They competed like maniacs," Harbaugh said of his players, "and now we've got another week of work."
It was a big day for the entire Harbaugh family, with Jim's older brother, John, coaching the Baltimore Ravens to an overtime win at Denver in the day's other divisional game.
"That was a real football fight," Jim said of the Ravens' 38-35 victory. "Had a chance to watch some of it before our game. Feel great for John and his team."
Despite it being his first postseason start, Kaepernick was unflappable, even after the pick-six interception to start the game. He came back on the next possession and orchestrated an eight-play, 80-yard drive that ended with his 20-yard keeper for a touchdown. That came on third and eight, and — unlike his longer touchdown — was not a planned run for him.
"Man-to-man coverage, they doubled Crab, broke down and I saw a running lane," the quarterback explained with a shrug.
Green Bay reclaimed the lead at the end of the first quarter with an 80-yard scoring drive that included a 44-yard pass to James Jones. Packers running back DuJuan Harris, who before he was signed as a free agent was selling cars in Jacksonville, scored on an 18-yard draw.
To the delight of their chilled crowd, the 49ers answered with consecutive touchdowns, both set up by Green Bay turnovers.
The first of those scores was a 12-yard pass from Kaepernick to Crabtree on third and goal. A muffed punt by Packers rookie Jeremy Ross led to San Francisco recovering the ball on Green Bay's nine.
The Packers' next possession ended with a deep, over-the-shoulder interception by 49ers cornerback Tarrell Brown, who turned and ran back the ball 39 yards to midfield.
Kaepernick drove the 49ers deep into Green Bay territory, and on third and nine scrambled up the middle for 15 yards to the Packers' nine.
However, he spiked the ball when he climbed to his feet and was flagged for unsportsmanlike conduct, wiping out the run yardage.
No matter. Two plays later, Kaepernick hit a diving Crabtree with a 20-yard strike for a touchdown and a 21-14 advantage.
Put simply by Green Bay receiver Greg Jennings: "We lost to a better team today."