49ers’ defense laid the groundwork for success

Reporting from Santa Clara, Calif. — The San Francisco 49ers didn’t wear their heart on their sleeve this season.

They wore it on their cover.

At the start of training camp, defensive players received binders with Justin Smith on the cover along with the numbers 0-1. The 11-year defensive end had played in one postseason game in his career, a loss when he was playing for the Cincinnati Bengals.

Explained Vic Fangio, San Francisco’s defensive coordinator: “Our main goal from the first day of training camp was to get him back in the playoffs and get that goose egg off the board. And we did that.”

Smith has been a key in that pursuit, which continues Sunday when the 49ers play host to the New York Giants in the NFC championship game, the first time since the 1997 season San Francisco has gotten this far.

It’s not just Smith, but the entire defense that has been the bedrock of the team’s foundation. For all the improvements of quarterback Alex Smith, and the consistency of the running game, it’s Fangio’s defense that gives the 49ers the best chance to knock off the Giants and return to the Super Bowl for the first time in 17 years.

The unforgettable play in Saturday’s 36-32 victory over New Orleans was Smith’s game-winning touchdown pass to Vernon Davis with nine seconds left. But among the signature moments leading up to that were safety Donte Whitner’s hit on Pierre Thomas that caused a fumble and sent the Saints running back to the sideline for the day, the 41-yard interception return by safety Dashon Goldson, and an utterly dominating play by Justin Smith on Pro Bowl tackle Jermon Bushrod.

In the fourth quarter, Smith caught Bushrod off balance and overpowered him, pushing the 6-foot-5, 315-pound lineman all the way back to quarterback Drew Brees. In reaching over Bushrod to grab the quarterback by the jersey, Smith forced Brees to rush a pass that fell incomplete.

Coach Jim Harbaugh said Wednesday the play by Smith is the type that has a ripple effect on the rest of the defense.

“Wicked fight,” Harbaugh said. “Other people see it and feed off of that. They want to rise to that level. Whenever you have a leader like Justin Smith — one of your best players, your hardest worker, your fiercest competitor, that bodes really well for your football team.”

In the late going of what had rounded into a tremendous defensive game, the 49ers gave up two huge plays — uncharacteristic of a unit that had given up an average of 10.9 points per game at Candlestick Park. The 49ers surrendered a 44-yard touchdown to running back Darren Sproles, who turned a short reception into six points, and a 66-yard touchdown pass to tight end Jimmy Graham.

Those breakdowns aside — and they came against two of the league’s most dangerous offensive weapons — the 49ers might be the surest-tackling team around. What’s more, San Francisco did not give up a rushing touchdown through its first 14 games.

Pro Bowl cornerback Carlos Rogers, in his first season with the 49ers, said that defensive success is as much about the team’s mentality as it is personnel.

“I’ve been on teams that have had a bunch of first-round draft picks,” said Rogers, who spent his first six seasons with the Washington Redskins. “Sean Taylor, LaRon Landry, DeAngelo Hall, Shawn Springs … and I haven’t had this much success in my career. It’s just about putting them games together back to back, making the best plays, and having your coach put you in a situation to win.”

In a sense, it all started when the 49ers got those playbooks in August with the tone-setting Smith on the front.

Can’t judge a book by its cover? That’s true. Usually.

sam.farmer@latimes.com

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