Seattle Seahawks quarterback Russell Wilson, right, avoids Green Bay Packer Ha Ha Clinton-Dix during the first half of Thursday night’s NFL opener. Stephen Brashear/AP)

The Seattle Seahawks wasted no time demonstrating that a repeat Super Bowl title this season is entirely possible, if not probable.

The Green Bay Packers have been celebrated as a top NFC contender this year, with quarterback Aaron Rodgers healthy and back in the lineup. But Rodgers and the Packers were no match whatsoever for the Seahawks in Thursday night’s NFL season-opening game in Seattle.

The Seahawks won, 36-16, and made it look easy. Their defense picked up right where it had left off in last season’s Super Bowl triumph over Peyton Manning and the Denver Broncos, sacking Rodgers three times and limiting him to 189 passing yards.

Rodgers didn’t throw a single pass in the direction of Seahawks cornerback Richard Sherman. So Sherman changed the game, taking away half the field from the Green Bay offense, even while appearing to do very little.

There were questions entering the season about the depth of Seattle’s defensive line after the unit suffered some losses during offseason roster reshuffling. But the Seahawks’ pass rushers kept Rodgers under duress all evening, and this Seattle defense very much resembled last season’s overpowering version.

The offense more than did its part. Tailback Marshawn Lynch ran for 110 yards and two touchdowns. Quarterback Russell Wilson was efficient, as always, with two touchdown passes and no interceptions. One of the touchdowns came on a clever play call in which Wilson threw the ball out of an option-running look. Wilson made certain to get wide receiver Percy Harvin, a potential difference-maker on offense as he returns from last season’s hip issues, involved early and often, with seven catches.

There is a group of potential NFC heavyweights that could challenge the Seahawks for conference supremacy this season. That group includes the New Orleans Saints, Philadelphia Eagles and San Francisco 49ers. It was thought to include the Packers, although their performance Thursday night cast doubt on that. The 49ers, even after three straight trips to NFC championship games and a Super Bowl appearance under Coach Jim Harbaugh, will have to prove that they still are in the Seahawks’ class this season, given that their defense will be without linebackers NaVorro Bowman and Aldon Smith for roughly half the season.

The Seahawks remain the class of the league, the team that everyone else in the NFL is chasing. They showed that Thursday night. The frightening thing is that there still is room for them to improve as the season progresses, particularly on offense. Wilson has been a highly efficient passer for two years, becoming the first quarterback ever to have a passer rating of 100 or above in each of his first two NFL seasons. But he hasn’t been a prolific passer, failing to reach even 3,400 passing yards in a season in an age in which a 5,000-yard season has become relatively routine. With Harvin back, Wilson might add some improved quick-strike capabilities to his already polished game.

The NFC playoffs could come down to which team, Seattle or New Orleans, secures the conference’s top seed for the postseason. Both teams are somewhere between extremely difficult and next to impossible to beat at home. The Saints have a bit of an advantage in that regard, playing in the kinder and gentler NFC South while the Seahawks must square off twice each with the 49ers, Arizona Cardinals and St. Louis Rams in the powerful NFC West.

The 49ers, not the Seahawks, have been the team that has seemed the best equipped in recent seasons to win a difficult playoff game on the road. But the Seahawks should be able to reach that level with their defense, with their running game, with a solid and ever-improving young quarterback.

They already have served notice that their crown will not be taken from them easily, if at all.