Seneca Wallace will start his second straight game in place of Hasselbeck

seneca scrambling in greeOnce again facing little pressure in the pocket, Peyton Manning is off to a strong start. The Indianapolis Colts’ defense, meanwhile, might have a tougher time getting to Matt Hasselbeck’s backup with Dwight Freeney injured.

With Manning coming off an outstanding game, the undefeated Colts may be forced to get by without their top pass rusher Sunday against the Seattle Seahawks, who will start Seneca Wallace in place of Hasselbeck for the second straight game.

Manning has managed to avoid heavy pressure throughout his career, and has been sacked only twice in three games this season. His passer rating is 117.7.

Manning wasn’t sacked last Sunday night, throwing three touchdowns in the second quarter and four overall to lead Indianapolis (3-0) past Arizona 31-10.

The three-time MVP completed 24 of 35 for 379 yards with one interception. He had four TD passes in a game for the 18th time, moving past Johnny Unitas for third on the all-time list behind Dan Marino (21) and Brett Favre (20).

Manning has topped 300 yards passing in each of his three games this season. He has seven TDs and two interceptions.

“The thing is that we constantly have to make certain that we don’t take it for granted,” Colts coach Jim Caldwell said. “He’s had some just unbelievable games. … I think he amazes us every time he does it, but he does it so often if you don’t watch yourself you can think that it’s commonplace, but it certainly is not.”

Indianapolis’ defense hasn’t been nearly as consistent. The Colts needed a late stand to preserve a season-opening victory over Jacksonville, then gave up 239 yards on the ground and couldn’t get off the field in a 27-23 win at Miami on Sept. 21.

Against Arizona, Indianapolis had perhaps its best all-around performance this season. Freeney had two of the Colts’ four sacks as the defense generated heavy pressure on the Cardinals’ Kurt Warner.

Freeney, though, hurt his right quadriceps on the last play of the third quarter and could miss two to three weeks. The veteran end, who recorded an NFL-best 16 sacks in 2004, has four of the Colts’ seven this season and leads the team with nine quarterback pressures.

His loss would be another blow for Indianapolis, which is already missing three defensive starters and is still learning coordinator Larry Coyer’s new system.

“They trust one another and give tremendous effort and it does not matter how many injuries we have, they step in and play well,” Caldwell said. “We just expect that next person to step in every single week and do the job.”

Former NFL defensive player of the year Bob Sanders (knee) still hasn’t practiced. The Colts were also without linebacker and captain Gary Brackett (knee) and cornerback Kelvin Hayden (hamstring) versus the Cardinals, although both may return Sunday.

Seattle (1-2) has its own injury concerns. The Seahawks were without Hasselbeck (broken rib) and six other starters during a 25-19 loss to Chicago last Sunday.

The 34-year-old Hasselbeck, hurt Sept. 21 at San Francisco, still can’t run and has pain when he takes a deep breath.

Wallace will start his second straight game in place of Hasselbeck. He set career highs with 26 completions, 44 attempts and 261 yards against the Bears.

Wallace will be operating behind a banged-up offensive line.

Left guard Rob Sims has a strained oblique and is questionable. If Sims can’t play, Mansfield Wrotto would likely become the eighth different player to start on the offensive line this season.

Brandon Frye, replacing Walter Jones (knee) at left tackle, played through a strained groin against Chicago. Seattle coach Jim Mora is hopeful he can go against the Colts.

Jones, a nine-time Pro Bowler, has had a slow road back from microfracture surgery last winter and will miss another game.

On defense, Seattle should get a much-needed boost from the return of Pro Bowl linebacker Lofa Tatupu, who missed one game due to a hamstring injury.

Seattle has given up a total of 48 points in two losses after beating St. Louis 28-0 in its opener Sept. 13. Opposing quarterbacks have completed better than 74.0 percent (40 for 54) of their passes in the Seahawks’ last two games.

Manning has two TDs and one INT in three games against the Seahawks, losing two. This will be the teams’ first meeting since Dec. 24, 2005, when Seattle won 28-13 at home.