ALLEN PARK, Mich. -- Detroit Lions coach Jim Schwartz admitted Monday that his team's season has "gone off the rails" and the progress made during last year's run to the playoffs has become a distant memory.
Schwartz, who has lost at least 10 games in three of his four seasons as Lions coach, said the blame for the team's unfulfilled 2012 expectations rests entirely with him.
"The ultimate responsibility of the team is (with) the head coach, and I need to do a better job," he said. "4-10 isn't good enough."
Detroit's 38-10 loss at Arizona on Sunday was its sixth straight and the team's most lopsided defeat since a 48-3 loss at Baltimore in 2009. It also bucked the trend: After defeating Jacksonville on Nov. 4, Detroit lost its next five games by an average of 5.2 points, only to get hammered by the Cardinals.
Tight end Tony Scheffler said the Lions had chances to overcome four turnovers and beat an Arizona team that was riding a nine-game winless skid.
"We never thought we were out of it," Scheffler said following the loss Sunday. "We just didn't make the plays to get back in it. Our defense fought hard the whole game. We didn't give them good field position. They kept us in it."
Schwartz's assessment of the loss differed sharply. After defending his team's play in recent weeks, Schwartz said the Lions simply made too many errors Sunday to be competitive.
"We've had a lot of games this year that came down to one critical play in the fourth quarter that you look at and say, 'Hey, if we made that one we would have won the game,'" he said. "We can't be naive to think that this was one of those games."
The Cardinals intercepted quarterback Matthew Stafford three times, two of which were returned for touchdowns. Stafford told teammates Sunday that he believed he was responsible for the loss after a 24-for-50 passing performance that was easily his worst effort of the season.
"That is about as bad as I can play," he said. "For us to be successful, I have to play a whole lot better than that. I understand that."
Schwartz praised Stafford's decision to take responsibility for the loss, saying "that's what good quarterbacks do," but he also reiterated his opinion that responsibility for the team's performance ultimately rests with the coaching staff. He also said he never considered pulling Stafford.
Calvin Johnson's play was Detroit's lone bright spot Sunday. Johnson made 10 catches for 121 yards despite facing coverage that Schwartz likened to a box-and-one defense in basketball.
"(Arizona) doubled Calvin (Johnson) on just about every play," he said." They used punt coverage to try to handle him and the fact that he still had 121 yards says a lot about Calvin, says a lot about (offensive coordinator) Scott Linehan's ability to still be able to get him the ball. But we severely lacked other playmakers on the field."
Johnson's 121 receiving yards Sunday give him 1,667 yards for the season, putting him 181 yards from breaking the NFL single-season record Jerry Rice set with San Francisco in 1995.
The Lions host playoff-bound Atlanta on Saturday.