Thanksgiving turned ugly in Detroit.
Any remaining goodwill between the Detroit Lions and Houston Texans melted away late in third quarter of Thursday's game when the Texans were awarded a touchdown on what should have been ruled a mundane 8-yard run by Justin Forsett. The touchdown proved to be very costly as the Lions went on to lose 34-31 in overtime.
Replays clearly showed Forsett's knee touch the turf, but he rose to his feet before the whistle blew, then bolted for the end zone. Officials ruled the play a touchdown, and Jim Schwartz was hot. The Lions coach launched his challenge flag onto the field, and that's where the trouble started for Detroit.
The NFL reviews every scoring play, but teams lose that benefit if the challenge flag is thrown. The Lions were flagged 15 yards for unsportsmanlike conduct, and it cost them dearly on the scoreboard.
"It's on me," Schwartz mouthed to his players and fellow coaches, pounding his chest over the mistake. The tone at Ford Field was volatile as fans rained down boos on the officials long after the commercial break.
The Lions' season is on the brink and bordering on lost -- and their fans don't want to hear this -- but the NFL has emphasized this rule to coaching staffs all season long.
We saw Mike Smith kill a promising drive for the Falcons in Week 11 when he tossed the red cloth on an Atlanta fumble that would have been overturned. Turnovers -- like scores -- are automatically reviewed, unless the head coach gets antsy with his little red friend.
Schwartz isn't likely to forget this rule again.
Follow Marc Sessler on Twitter @MarcSesslerNFL.