What it means: The Lions spent three quarters looking like they were about to win their first playoff game since the 1991 season. Then, everything began to unravel for Detroit, in a fashion they haven't seen since last season.
The defense, which had been the key to the Lions' entire season, made big errors on a fourth-quarter drive that was set up by a shanked Sam Martin punt. The offense, which moved well in the first half, sputtered in the second and had a drop and false start from star receiver Calvin Johnson on the game's final drive.
With those miscues coming again, the Lions' hopes of advancing in the playoffs for the first time in over two decades died along with them. Detroit finishes one of the best seasons in its history at 11-6.
Stock watch: Remaining in neutral -- Matthew Stafford. He threw one bad pass -- and was bailed out when the Dallas defender dropped the interception. Otherwise, Stafford was smart and efficient, completing 28 of 42 passes for 323 yards, one touchdown and one interception. He also had a critical run early where he shook off a Cowboys defender for a first down. He fumbled twice on the Lions' final drive.
Falling -- Sam Martin. He had a good game up until the fourth quarter, when he shanked a massive punt -- sending the ball only 10 yards and setting up the Cowboys' winning drive. It was reminiscent of a punt Martin had against Cincinnati during his rookie season, when his shank helped set up the Bengals' winning drive. It looked like he hit the ball off the side of his foot.
Falling -- The Lions' defense. It was a group that held together well all season despite injuries to key players and having to rotate players all over the place. Yet on the game's critical drive -- the season's critical drive -- the Lions committed two defensive holding penalties and gave up a fourth-down completion to extend the drive that led to the Cowboys' winning touchdown.
Game ball: Ndamukong Suh. The All-Pro has had the most consistent season of his career, but Suh was almost not allowed to play in this game. The NFL's overturning of his suspension on Tuesday might have set the tone for everything that followed. Suh was massive for the Lions when it counted -- sacking Tony Romo on back-to-back plays to stall a critical Dallas drive.
What's next: Detroit's season ends.