SAN FRANCISCO The San Francisco 49ers' 2013 fortunes could have taken a drastic turn for the worse when Colin Kaepernick got hit late and out of bounds by Packers linebacker Clay Matthews in Sunday's season opener.
Kaepernick's mesmerizing response: He passed for a career-high 412 yards and three touchdowns in a 34-28, come-from-behind win over Green Bay.
"If intimidation is your game plan, I hope you have a better one," Kaepernick said.
Frank Gore's 1-yard touchdown run put the 49ers ahead for good with 5:47 remaining, providing yet another fourth-quarter comeback at storied Candlestick Park, the 49ers' home for a 43rd and final season.
Anquan Boldin and Vernon Davis keyed Kaepernick's career-best passing day, which came in a fiery rematch of January's divisional playoff game when Kaepernick led the 49ers to victory with the best rushing day in NFL history by a quarterback (181 yards).
Boldin, who in February helped the Baltimore Ravens beat the 49ers in Super Bowl XLVII, had a dazzling debut in a 49ers uniform: 13 receptions for 208 yards and a touchdown. Davis came through with six catches for 98 yards, and his two touchdown catches were sandwiched around Boldin's second-quarter score.
Boldin and Davis figured to be Kaepernick's top targets this season once Michael Crabtree got sidelined with a torn Achilles in May.
But to do that Sunday, Kaepernick (27-of-39 passing, 129.4 rating) needed to survive Matthews' second-quarter hit that sparked a sideline scuffle and immediately preceded Boldin's 10-yard touchdown catch.
"That's football. You expect to get hit," Kaepernick said.
"Kap likes that," right tackle Anthony Davis added. "I don't as his protector, but he likes the physicality of it."
On third-and-6 from the Packers' 10, Kaepernick scrambled 4 yards to the left sideline and was a stride out of bounds when Matthews jumped on his back like a cape. Matthews slammed Kaepernick to the ground, and the 49ers' prized quarterback landed hard on his back.
"I had already committed to hitting the quarterback," Matthews said. "I guess I should have figured he was going to step out of bounds, but it was nothing personal. I went up to him later and was joking around with him. Not a very smart play."
Players from both teams converged on the scene, and although Matthews got called for a late-hit penalty, it was offset by an ensuing unsportsmanlike-conduct call on left tackle Joe Staley.
So, on third-and-6 again from the 10, Boldin lined up left and cut across the middle of the field for his touchdown and a 14-7 lead 8:57 before halftime. Head referee Bill Leavy admitted after the game that it should have been a fourth-and-2 play, citing that Matthews' and Staley's penalties were "dead ball" infractions.
Kaepernick went on to post the 11th-highest passing-yardage total in 49ers history. It was his first 400-yard game since his freshman year at Nevada and the 49ers' first since Tim Rattay in 2004.
"Really special performance by him," 49ers coach Jim Harbaugh said. "Some laserlike throws down field. Pinpoint accuracy. Managing the chaos of a game. Never blinked, never flinched."
The Packers were intent on making Kaepernick beat them through the air and take away his read-option runs that throttled them in the playoffs. Kaepernick obliged, and his only carry on a read-option fake resulted in a 7-yard loss, with Matthews making the tackle.
"Colin Kaepernick throws as good or better than anybody I've ever seen on the run," Harbaugh said of Kaepernick, who got sacked twice.
Kaepernick and the Packers' Aaron Rodgers each threw three touchdown passes before the NFC rivals entered the fourth quarter tied at 21.
The Packers took their first lead with 8:26 remaining Eddie Lacy's 2-yard touchdown plunge but the 49ers answered in less than three minutes with Gore's touchdown.
Boldin came through with a 43-yard catch-and-run on that go-ahead drive, and he made a 15-yard reception on fourth-and-2 on the next series, which ended with Phil Dawson's 33-yard, last-minute field goal.