The league said officials should have stopped play and eliminated confusion about the down and distance at the end of the Giants' 24-17 victory at Washington.
"I talked to Dean earlier today, he gave me a call and just went over the scenario," Shanahan said, referring to Dean Blandino, who oversees NFL officiating. "Obviously they made a mistake and you live with it."
With New York leading by seven points just after the two-minute warning, a catch by the Redskins' Pierre Garcon on second-and-5 was spotted short of a first down at the Washington 45. Referee Jeff Triplette signaled third down. But the head linesman, with the Redskins in a hurry-up offense, incorrectly motioned for the crew to advance the chains, which caused the down boxes to read first down.
"In this situation where there is obvious confusion as to the status of the down, that play should have been stopped prior to third down and the correct down communicated to both clubs," Blandino said Monday in a statement. "This should have occurred regardless of the fact that Washington had no timeouts and it was inside two minutes."
Only the referee can rule and signal a first down. The official nearest to the down markers and chain crew, the head linesman, is required to wait for that first-down signal from the referee before moving the chains. That did not happen at FedEx Field.
After Washington's incomplete pass on the next play—which many Redskins believed was on first down—the chains were moved back and the down boxes correctly reset to fourth down.
Blandino said instant replay review was not used on Garcon's catch because the replay official determined the ball was "correctly spotted short of the line to gain for a first down."
Shanahan was asked if he would be in favor of scrapping the chains and using laser technology to help spot the ball.
"You talk about it at the owners' meeting, kind of go through the variables, exactly how accurate it is and how it would be implemented," he said. "I think there's a lot of technology that you could possibly use, but before you do that you go through all the situations and find out if it's effective and how effective."
Redskins quarterback Robert Griffin III said the confusion affected the play calling.
"The chain said first down, and then when we came back, we think it's second-and-10, and they're yelling out it's fourth down," Griffin said. "No explanation. No measurement. Didn't stop the clock to allow the chains to move back. And we just had to go ahead and call the play."
Griffin did complete a 6-yard pass to Garcon on fourth-and-1, but safety Will Hill stripped the ball. The Giants then ran out the clock.
"I told him I wanted a measurement because I knew it was close," Shanahan said, not specifying which official he was referring to. "It was inches. And he said, 'No, it's a first down.' And he moved the chains. And then after I saw it was fourth down, I asked him, 'You already told me it was first down.' He didn't say anything. So that was quite disappointing."
Speaking to a pool reporter Sunday night, Triplette said: "We signaled third down on the field. The stakes were moved incorrectly. After that play, we said it was still third down. We had signaled third down prior to the play starting. The stakes just got moved incorrectly."
Triplette defended not stopping play, saying it would have given an "unfair advantage." But Blandino said Monday that was the wrong decision.
Giants defensive end Justin Tuck, who played every snap, said he was aware it was not a first down.
"I remember turning to the referee and saying, 'That's not a first down,' '' Tuck said Monday. " Obviously, they're hurrying up, you don't really have time to argue it.
"I think at the end of the day, it was actually the right call. It might not have come across in the right manner, but I think it was the right call. And when the ball is getting snapped that fast, it's very tough for a referee to get all of these calls right."
AP Sports Writers Joseph White and Tom Canavan contributed to this report.
AP NFL website: http://www.pro32.ap.org