The Seahawks will look to be the 1st repeat Super Bowl winners since the Patriots in 2004 and 2005.The Seattle Seahawks enter the 2014 season as the top-ranked team in ESPN.com’s weekly NFL Power Rankings.

The Seahawks have plenty to boast about after a 13-win 2013 season, which was capped off by a 35-point victory over the Broncos for the franchise’s first Super Bowl victory.

Many of the key pieces from last year’s team are returning in 2014, which begs the question… How long can the Seahawks stay No. 1?

What hasn’t changed

The Seahawks’ biggest strength last season was their defense. Seattle finished with the fewest points allowed, the fewest yards allowed and the most turnovers forced. No team had completed that trifecta since the 1985 Chicago Bears.

The Seahawks made sure to lock up key members of the secondary, signing cornerback Richard Sherman and safety Earl Thomas to extensions.

The Seahawks had the lowest opponent Total QBR (29.0) last season and limited opponents to a league-best 5.8 yards per pass attempt. Seattle also led the league in interceptions (28), bolstered by Sherman’s league-leading eight.

Offensively the Seahawks still have Russell Wilson at quarterback and after a brief holdout, Marshawn Lynch at running back.

Most Yds per Attempt – Last 2 Seasons

The Seahawks have been the most run-heavy team the past two seasons with that duo in the backfield. Since joining the Seahawks in Week 6 of 2010, only Adrian Peterson has more rushing yards and rushing touchdowns than Lynch.

When Wilson does pass, he makes the most of his opportunities. He is averaging 8.1 yards per attempt in his career, third-best in the NFL during that time. That average is bolstered by Wilson’s league-best 51.3 completion percentage on passes thrown 15 or more yards downfield.

What has changed

The Seahawks did lose key pieces to both their defense and offense in the offseason.

On the defensive side, the Seahawks lost three members of the defensive line in Chris Clemons, Red Bryant and Clinton McDonald. The Seahawks sacked or put opposing quarterbacks under duress on 31 percent of dropbacks last season, best in the NFL, and were able to do so with a deep rotation.

Seattle had eight defensive linemen record between 500 and 700 snaps last season, including the three they lost. The Seahawks brought in 34-year-old defensive tackle Kevin Williams in free agency, and didn’t address the d-line until the fourth round in the 2014 NFL Draft.

The Seahawks also lost Wilson’s favorite target in Golden Tate this offseason. Wilson targeted Tate 44 times more than the next highest Seahawks receiver the past two seasons (including playoffs), completing 67.8 percent of his attempts to Tate with 13 touchdowns and only two interceptions.

The Seahawks used a second-round pick (Paul Richardson) and a fourth-round pick (Kevin Norwood) on wide receivers, but the big change for Seattle’s offense may be a healthy Percy Harvin.

Including playoffs Harvin played a mere 59 offensive snaps for Seattle last season, but he led all players with 137 all-purpose yards in the Super Bowl. Harvin gained the second most yards after catch the first four years of his career, so if he stays healthy he could become Wilson’s new favorite target.

First 3 Games

The Seahawks start their 2014 season with three straight playoff teams from 2013: the Packers, Chargers and Broncos. The starting quarterbacks for those teams all finished in the top six of Total QBR last season. But if the Seahawks’ defense continues to produce at an elite level, Seattle could find themselves No. 1 for a while.