The Arizona Cardinals were the best team in the NFL the first half of the season and had remained perfect on the road even after stumbling in recent weeks, leaving them in position to clinch a playoff berth with a win Sunday.
Instead, the Cardinals turned in their most disappointing performance of the season, getting blown out 30-12 by a Detroit Lions team that had entered the game with an NFL-worst 1-11-1 record.
So it was that an Arizona team that opened the year 7-0 slumped to 10-4 after a defeat no one saw coming.
"This is an unacceptable loss," Cardinals linebacker Jordan Hicks told reporters. "We weren't ourselves today."
Added quarterback Kyler Murray: "They were hungrier than us. They played harder than us."
It was a performance reminiscent of the Cardinals' ugly 34-10 home setback against the Carolina Panthers last month, but all the more galling given the quality of the opposition.
The Lions were even colder than the Cardinals were hot to open 2021, dropping their first eight games before playing to a 16-16 draw with the Pittsburgh Steelers, then losing two more before finally beating the Minnesota Vikings two weeks ago.
Yet Detroit managed to dominate the proceedings Sunday even though the teams finished the game virtually level in terms of key statistics.
The Cardinals out-gained the Lions 398-338, while Detroit held a slight edge in time of possession (31:52 to 28:08) and each team had just one turnover.
Yet Arizona failed to convert on all four red-zone opportunities, most notably turning the ball over on downs at Detroit's three-yard line after a failed fourth-down try late in the first half.
Goff engineered a 97-yard touchdown drive from there, giving the Lions a 17-0 lead at half-time, and Detroit never looked back.
Arizona, meanwhile, may have tried to do too much after getting in that hole.
"There's no such thing as a 17-point touchdown and we've got to approach it that way if we get in this situation again," said head coach Kliff Kingsbury.
Arizona had won all seven of their road games this season by double digits entering Sunday, and they face one more daunting test away from home, a trip to the NFC East-leading Dallas Cowboys in two weeks' time.
They can only hope to figure out what adjustments need to be made before facing that challenge.
"We know who we are," Murray said. "We know the guys we have in the locker room, we've got the talent, we've got the coaches, we've got the leadership. It's about locking in and playing to our capabilities.
"Screw everything else, pretty much. We have to be how we were at the beginning of the season."