Lovie Smith dropped the ball by not dropping the flag.

The Chicago Bears coach, in a rare admission of error when it comes to football strategy, admitted Monday that his failure to challenge a fumble by Jay Cutler on a quarterback sneak Sunday at Soldier Field was a critical element in the team’s 17-14 loss to the Washington Redskins.

It was the third loss in four games for the Bears (4-3), who opened the season 3-0.

Smith had failed with the red flag on the previous play when wide receiver Earl Bennett was tackled on the one-yard line after a 48-yard gain. Smith challenged that Bennett got into the end zone, but a replay review clearly showed Bennett’s left knee was down before he reached the goalline.

Following the timeout, the Bears came out in a jumbo set and Cutler got upright quickly after taking the snap and jumped, extending the ball over the pile. He was hit by Redskins defensive tackle Albert Haynesworth and then linebacker London Fletcher jarred the ball loose. Washington recovered.

Replays showed the ball crossed the plane of the goalline, but the Bears, who led 14-10 at the time, did not challenge the play. The game was three minutes into the second half, and Smith knew if he failed on the challenge, he would be out of challenges and down to only one timeout for the remainder of the game. It proved to be the difference in the game.

“Yes, I should have (challenged the play),” Smith said. “Normally, if there's a critical situation I throw it whether I have a good look or not. I didn't have a great look on it. I need to be able to make that call.”

Mike Pereira, the NFL’s former vice president of officiating and now an analyst for Fox Sports, was surprised Smith didn’t challenge the play.

“I am flummoxed that the Bears would choose to challenge the previous play and not this one,” Pereira wrote in his column. “We can talk all day about officiating mistakes and the impact they have on a game, but this was clearly a mistake by Smith and his coaches that may have cost them the game.”

Smith is 1 for 5 on replay challenges this season and 3 for 15 over the last 23 games.

“I thought we were in control of the game,” Smith said. “We've given the opponent the ball at the one-yard line before and forced them to punt it and I felt like we would get the ball back right away, which we did, and we failed to get it back down.”

It wound up costing them.

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Brad Biggs covers the Bears for the Chicago Tribune

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