SEATTLE (AP) After 15 games, the only certainty about the Seattle Seahawks is to expect inconsistency.
Even coach Pete Carroll can't be sure of what kind of performance he's going to get from a team that's bound for the playoffs for the fifth straight year.
''I don't know. I keep thinking we're going to do right, we're going to do well,'' Carroll said.
The latest example of Seattle's maddening unpredictability came Saturday in a 34-31 loss to the Arizona Cardinals that severely damaged the Seahawks' hopes of landing the No. 2 seed in the NFC and a bye in the playoffs. With the chance at keeping control of the No. 2 seed and the fourth perfect home record in franchise history, the Seahawks played so poorly in the first half that a second-half offensive eruption couldn't make up for the early mistakes.
Seattle (9-5-1) fell behind 14-0 and trailed 31-18 late in the fourth quarter. There were mistakes all around, from the offensive line being unable to protect Russell Wilson, to the secondary giving up an 80-yard touchdown, to two blocked kicks and a missed extra point.
They were all flaws the Seahawks nearly overcame thanks to four touchdown passes by Wilson in the second half, including two in the final three minutes as Seattle pulled even at 31. But they are glaring issues for a team many thought would be the biggest threat to Dallas in the NFC.
''It just sucks that we lost in that manner,'' Seattle defensive end Cliff Avril said.
Arizona (6-8-1) was able to take enjoyment out of damaging Seattle's playoff plans and finally coming out on top in a close game. The Cardinals had five losses of seven points or less, along with their 6-6 tie against Seattle earlier in the season. Saturday was just Arizona's second win by less than eight points.
''I don't know. It's just one of those weeks where we felt like we were going to win,'' Arizona quarterback Carson Palmer said.
Even on a team with a losing record, David Johnson strengthened his case for postseason awards. Johnson finished with 136 yards from scrimmage, his 15th straight game with at least 100 scrimmage yards, the longest streak to start a season in league history. He had three short TD runs, giving him 20 total touchdowns for the season, the first player since LaDainian Tomlinson in 2006 with 20 TDs and 1,000 yards rushing.
And yet his two biggest plays came as a receiver. Johnson had two receptions for 42 yards on Arizona's final drive that was capped by Chandler Catanzaro's 43-yard field goal on the final play.
''You run out of superlatives to describe him,'' Arizona wide receiver Larry Fitzgerald said. ''He does something special every single game we play. ... The guy continues to carry the load every week.''
Other observations from Seattle's third loss in its past four home games against the Cardinals:
INJURY CONCERNS: Seattle lost wide receiver Tyler Lockett to a gruesome lower right leg injury in the second quarter. Lockett was landed on awkwardly by defensive back Brandon Williams near the goal line. He had an air cast applied on the field and was taken off on a cart. Carroll did not have an exact diagnosis, but said Lockett would have surgery and be out for the season.
''I got close to him and there was blood everywhere near his ankle and stuff. That was an ugly situation,'' Wilson said.
Seattle also lost running back Thomas Rawls to a bruised shoulder. He did not play in the second half.
SACK ATTACK: Arizona sacked Wilson five times in the first half and six overall. The six sacks were the second most this season by Arizona, topped only by the seven it had against San Francisco in Week 5. Markus Golden had two sacks, giving him 10 for the season. He's the first Arizona player with at least 10 sacks since John Abraham in 2013.
BALDWIN'S BREAKOUT: With Lockett out, Doug Baldwin had the best game of his career. Baldwin finished with 13 catches for 171 yards and a 42-yard touchdown in the fourth quarter. Baldwin was targeted 19 times, the second most by any player in the league this season. He was also credited with two running plays that were ruled backward passes.
''He just did everything,'' Carroll said.
CENTURY MARK: Fitzgerald had four catches to give him 102 for the season. It's the fourth 100-catch season for Fitzgerald, who leads the NFL in receptions. Fitzgerald had one catch for 3 yards in the first half, and got his 100th reception of the year on a diving 16-yard reception to the 1-yard line on the first play of the fourth quarter.
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