Because they were already trailing the NFL's fifth-best defense 17-10, Kelly thought that points would be at a premium, so he opted to go for it on fourth down. Following a timeout, Kelly sent out his personnel grouping and the Cardinals immediately countered with a timeout of their own.
"Did the play call change? Our call was the same but the defense changed," he said.
So the defense may have anticipated the call?
"I think so. It was just a good play by them. We didn't execute like we should have."
The Eagles' call was also not an unfamiliar one and was unsuccessful earlier this season in similar situations, though it is hard to devise so many variations on a gut-check outside zone play designed to get a yard. Theoretically, Ryan Mathews is a big enough running back to lean forward and theoretically, his offensive line can clear just enough of a path to make it happen.
"We ran outside zone and I guess we didn't execute the way we should have," Johnson said. "All the interior guys were just root-hoggin' and we had no choice but to pin those guys down."
Taken independently, this could be just another head-scratching moment completely independent of the last. But when looked at through a wider lens, it may be the latest piece in a confounding puzzle that Kelly has created for himself down in Philadelphia. The Eagles lost 40-17 on Sunday night despite being gifted every opportunity to stay in the game. Sam Bradford played reasonably well. Mathews gained more than five yards per carry. Jordan Matthews caught eight balls for 159 yards and a touchdown.
So why are the team's faults and mistakes and setbacks so difficult to explain? And, with a scenario in place that would take them to the playoffs if they win out -- they play the Redskins at home Saturday night on NFL Network -- can they eliminate enough of the confusion to find away into the postseason?
"I think everyone is a little bit frustrated after the way we played tonight," Bradford said. Obviously, we thought we were taking steps in the right direction."
Heading into Sunday night, DeMarco Murray converted 100 percent of his third- or fourth-and-1 attempts as an Eagle. He also prefers to run under center, and on that particular fourth down play, Bradford happened to be right up against the line. On that failed conversion, though, Murray was on the sideline. He finished the game with two carries for three yards and spent a large portion of the second half donning a ski cap on the Philadelphia sideline.
He was, once again, asked about whether or not he wants to be here. Clearly he doesn't, and clearly Kelly doesn't want him, but $18 million has a way of bringing people together.
"The plan was we were going to rotate the running backs," Kelly said. "We didn't run the ball as much as we wanted to run the ball but we rotated three guys. We only played three tonight." Was there a reason he only had two carries?
"I expected us to run the ball better, so obviously, the more carries you have, the more you can distribute that," he said. "So again, and you get behind and it turns into a little bit more of a throwing game, so that's what kind of happens in those games."
And it wasn't just moments related to the offense and their seldom-used $40 million player. The defense was drifting into sub packages with their backs against the goal line. Their line and secondary was so scattershot that the Cardinals didn't even bother taking advantage of the fact that the Eagles were down to their final two healthy cornerbacks, opting to pound the ball with David Johnson.
Set against the backdrop of Bruce Arians' team, where everything has a certain beauty and reasoning behind it, where every play seems to yield an open receiver and each skill position player passes the baton to the next, it's hard not to wonder if we expected too much out of Kelly after two consecutive 10-win seasons.
The ease with which his offenses used to operate is gone, leaving us all wondering how certain people -- and coaches -- can make it look so easy.