On a Sunday night seven weeks ago, the Arizona Cardinals pulled off a 39-32 victory over the Seahawks in the din that is CenturyLink Field.
They haven't lost since.
It was a turning point for the Seahawks as well. After the loss, they reeled off five straight victories to clinch a playoff berth before stumbling last week at home against St. Louis.
Possible playoff seeding is all that's at stake when the teams meet in their regular-season finale Sunday.
Arizona (13-2) has won nine in a row and, with its 38-8 blowout of Green Bay last Sunday, has clinched a first-round playoff bye. The Cardinals can get the No. 1 seed, and home-field advantage throughout the NFC playoffs, with a win on Sunday and a Carolina loss to Tampa Bay.
The Seahawks (9-6), two-time defending NFC champs, are the No. 6 seed as of today, but would move up to No. 5 with a win over Arizona and a Minnesota loss at Green Bay.
In that Nov. 15 win at Seattle, Arizona bolted to a 19-0 lead, then fell behind 29-25 before scoring two late touchdowns, the winner coming on Andre Ellington's 48-yard run with 4:04 to play.
"To have a lead, give up a lead, and then just score 14 points in the (fourth) quarter there against that crew, just shows that we've got a very resilient group," Cardinals quarterback Carson Palmer said, "and we believe in ourselves, and we believe in each other."
Neither Arizona coach Bruce Arians nor Seattle coach Pete Carroll entertained any thought of resting players for the playoffs.
"It's not a finished product, and then you go and play in the playoffs," Carroll said. "We keep working to improve every week, and that's what we're trying to do this week. It's such a good opponent and they're so loaded up in so many areas that they make us have to play well."
Arians said the Seahawks have changed since that mid-November meeting.
"A bunch more empty backfield sets. Throwing the ball a lot more," he said.
Arians has never beaten the Seahawks in Arizona.