RENTON — Four months may not seem like a long time, but in an NFL season, so much can change from September to January.

Even though many believed before Seattle and Green Bay faced each other in the season opener that they might play a second time this season in the NFC championship game, the roads these two teams traveled between that Thursday night opener and Sunday’s NFC championship game have been anything but predictable.

The last time these teams saw each other, Percy Harvin was one of the key figures in Seattle’s offense, and rookie receiver Davante Adams wasn’t a part of Green Bay’s offense. Now, Harvin is a New York Jet, and Adams was his team’s leading receiver in Sunday’s playoff win.

Green Bay’s defense has progressed significantly since that game, and its offense has been more consistent since a 1-2 start. Then again, the Seahawks have also taken big strides over the past four months, culminating in a six-game winning streak to close the regular season, which allowed them to take the No. 1 seed from Green Bay and Dallas.

And back in early September, Packers quarterback Aaron Rodgers had yet to tell panicking Packers fans to “R-E-L-A-X,” Seahawks receiver Doug Baldwin hadn’t called out his offense in a profanity-laced rant, running back Marshawn Lynch hadn’t said “yeah,” “I appreciate you asking about my stomach,” or “I’m thankful,” Packers running back Eddie Lacy was in a sophomore slump and safety Earl Thomas had yet to set off a walk-through scuffle that would lead to a season-changing team meeting.

So just because the Seahawks rolled to a 20-point victory over the Packers in Week 1, that doesn’t mean this weekend’s game will play out in a similar fashion. Yes the Seahawks are a heavy favorite to return to the Super Bowl, and for good reason — they are the more talented, more balanced team, and they’re playing at home. But they also know they’ll see a different team than the one they faced in the season opener, and they also know they too have undergone significant change.

“They’ve really turned their season around statistically in some really obviously areas from the first eight games to the second eight games,” Seahawks coach Pete Carroll said. “Their rushing stats on both sides have gone way up on offense and gone way down on defense.”

As Carroll notes, the Packers have made strides in the running game on both sides of the ball. Lacy, who was so impressive as a rookie, opened the season by rushing for just 34 yards against Seattle and he was held under 50 yards each of his first four games. He has finished the season strong, however, gaining 97 or more yards in six of the past seven games.

Perhaps most importantly for the Packers as they set to face the league’s leading rushing attack, they’ve held four of their last nine opponents under 100 rushing yards, with a high of 145 allowed, after giving up 100 or more in their first eight games, including three games of 207 (Seattle), 235 and 193 rushing yards allowed.

“I think we’re a lot different team,” Packers defensive coordinator Dom Capers told reporters in Green Bay.

Both teams respect their opponent in Sunday’s game, and both teams feel like they’ve changed and improved since they last saw each other. For the Packers, the question will be whether or not they’ve made up enough ground on the defending champs to beat a team that handed them one of their worst losses of the season.

“Our younger players have really improved since then,” Packers coach Mike McCarthy told reporters. “I think we’ve really improved as an offense. Our offensive line is playing at a high level.

“Hey, we scored a few points this year. They’re a great defense. We recognize that, but we like a challenge.”

The Seahawks have lost a few key players to injuries since then — fullback Derrick Coleman, one of 15 players on injured reserve, scored Seattle’s final touchdown — and they traded one of their most talented players, but by almost any measure they’re playing their best football at the right time of year.

If the Seahawks are on top of their game, they’re nearly impossible to beat at home, but as much as Green Bay also improved as the season has gone on, the Packers should pose more of a threat than they did four months ago.

“They’ve gone through a transition during the course of the season that has really turned them into playing great football here at the end,” Carroll said. “As we went against them in the opener, we thought this was the team we would be playing like right now, so it’s matched up pretty well.”