49ers doing the little things to go 4-1

The difference in NFL victory and defeat can be as simple as a little extra effort.

For instance …

Taking the extra step to wrap up a powerful ballcarrier in the open field, as San Francisco 49ers linebacker Patrick Willis did in a 13-tackle performance.

Exhibiting more caution and discipline in passing, as the previously reckless Alex Smith has done to improve his passer rating to the second-best in the NFC.

Having confidence, as defender Carlos Rogers did after a turnover, telling Coach Jim Harbaugh, “Don’t worry, we’ll get it right back,” and then intercepting a pass.

The 49ers started 0-5 last year. Now, with rookie coach Harbaugh’s message of “solid, very good football with great effort” resonating, the 49ers are 4-1 as they head back to their coach’s college home state of Michigan on Sunday to take on the undefeated Detroit Lions.

“This league is hard, it’s tough,” Harbaugh told reporters Monday after reviewing the film of his team’s 48-3 dismantling of visiting Tampa Bay. “These games are three-plus hours of … painful times. It can be like sitting in a dentist’s chair. This kind of game [at the Lions] epitomizes that kind of struggle.”

The NFL’s attention to parity is shining again, with all eight divisions claiming either a different leader than last year’s champion or a new team tied for first.

The 49ers and Lions were a combined 1-9 last year at this point.

“The focus is on the details, football, teaching,” Smith said, shedding the reputation of his past work (51 touchdowns, 53 interceptions) to efficiently throw for seven touchdowns and only one interception for 963 yards this season. “We’re getting better every day.”

It helps being able to hand the ball to a top-10 running back such as Frank Gore, who ran for 125 yards in the romp over the Buccaneers. It was the franchise’s most lopsided triumph since the Joe Montana-led 55-10 victory over Denver in Super Bowl XXIV.

San Francisco’s defense has been tremendous, ranked fourth against the run, 13th overall, third in interceptions and seventh in points given up.

Harbaugh said playing the unbeaten Lions, who beat Chicago on Monday night, 24-13, will keep his team’s full attention.

“They understand the volume, the nature of this game,” Harbaugh said.

Directing the organization’s best start since 1956, Detroit quarterback Matthew Stafford is bracing.

“That’s the way the league is … 16 games, and we’ve only played five,” Stafford said. “We’ve got a tough team coming in.”

Other games:

Buffalo (4-1) at New York Giants (3-2)

Upstate versus Uptown, with two of the league’s top-10 passers (Ryan Fitzpatrick and Eli Manning) squaring off. The Bills lead the NFL with 16 takeaways.

Dallas (2-2) at New England (4-1)

The Cowboys have a difficult task trying to defeat Tom Brady at Gillette Stadium, but they’ve had a week to help figure out how to boost a run game overshadowed by Tony Romo’s passing yards — and mistakes. Dallas’ front seven is solid, ranking first against the run. They need to translate that to a pass rush against Brady, the league’s passing yardage leader.

Houston (3-2) at Baltimore (3-1)

A battle of AFC division leaders. The intense Ravens defense is rested from an off week and has its sights on Houston quarterback Matt Schaub, who — without injured star receiver Andre Johnson for the first time — looked winded in throwing a decisive goal-line interception in Sunday’s loss to the Raiders. The Texans also lost defensive end Mario Williams, the first pick of the 2006 draft, to injury.

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