NFL Week 6 preview: 49ers have ‘unfinished business’ vs. Giants

The last two teams to face San Francisco were speed bumps.

Sunday, the 49ers face last season’s Super Bowl roadblock: the New York Giants, who advanced to the game’s biggest stage with an overtime victory in the NFC championship game at Candlestick Park.

But these are different 49ers, a 4-1 team that outscored the last two opponents — the Jets and Bills — by a combined 79-3, and are fresh off a club-record 621-yard offensive outburst against Buffalo.

Now, the 49ers have a chance to dispatch the Giants, the team that denied them a trip to Super Bowl XLVI. Sunday’s game also will be played at Candlestick.

“There’s a lot of baggage, a lot of history there,” San Francisco quarterback Alex Smith said Monday. “A little unfinished business, I guess.”

Smith has gone from caretaker quarterback to legitimate playmaker, and came out of the weekend with the league’s best passer rating, 108.7.

“I can’t tell you how much respect I have for him,” said 49ers Coach Jim Harbaugh, a former NFL quarterback. “He plays so well, handles himself. He does all the things. I look back and say, ‘I wish I could have done as good a job as he’s done on and off the field.’”

The 3-2 Giants, meanwhile, are no pushovers. After falling behind early on Sunday, they came back to pound Cleveland, 41-27, with 27 unanswered points over the second and third quarters.

New York ran for 243 yards, including a career-best 200 by Ahmad Bradshaw. It was the team’s most yards rushing since gaining 301 against Carolina in 2008.

The 49ers had the league’s best run defense in 2011, and have dropped off only slightly this season, ranking seventh in that category in giving up 81.4 yards per game.

Western shootout

San Diego plays host to Denver on Monday night, and that always makes for an interesting game. Throw in Peyton Manning, and it’s a must-watch matchup.

The Chargers have had a lot of success against Manning, beating Indianapolis in five of their nine meetings with him starting at quarterback.

Manning has thrown 17 touchdown passes with 17 interceptions against the Chargers since he was a rookie in 1998, and he has been on the losing side in five of the last six meetings.

The stakes are high for both teams, as San Diego is looking to maintain its one-game lead in the AFC West, and Denver is trying to recapture the momentum it built in rolling over Oakland two weeks ago.

Pete vs. Pats

New England plays at Seattle on Sunday, marking a reunion of the Seahawks’ Pete Carroll and the franchise he coached from 1997 to ’99. The game also pits the NFL’s No. 1 offense (New England) and defense (Seattle).

For the Seahawks, the biggest question is whether they plan to stay the course with rookie quarterback Russell Wilson — one touchdown and five interceptions over the last two weeks — or try Matt Flynn, the coveted free agent signed in the off-season.

Flynn, who spent the last four seasons backing up Aaron Rodgers in Green Bay, made the first start of his career against the Patriots when Rodgers was recuperating from a concussion in late 2010. Flynn was impressive in the 31-27 defeat, throwing for three touchdowns with an interception.

Opportunity knocks

With New Orleans winning Sunday night, Cleveland is the only NFL team without a victory. The Browns play host to Cincinnati on Sunday in what could represent one of their few remaining chances to pick up a win.

That’s not to say beating the Bengals is easy by any means, but the Browns are getting cornerback Joe Haden back after four games without him, and he’s the best player in their secondary. Then again, Haden was burned by receiver A.J. Green in both losses to the Bengals last season, losing the touted rookie-vs.-rookie matchup.

The Bengals are coming off a sputtering performance at home in a 17-13 loss to Miami.

sam.farmer@latimes.com

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