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One of the reasons that the 49ers' defense improved coming out of their Bye week in the regular season was inserting Ambry Thomas into the lineup.

Before he was out there, the 49ers were running Deommodore Lenoir outside with Isaiah Oliver in the slot. That was a recipe for disaster as Oliver would give up more plays than he would make. So, the 49ers went with Thomas on the outside for nickel packages with Lenoir kicking inside. And boy, did that change pay off. Suddenly, the 49ers were stickier in coverage and it allowed the pass rush to be more effective. 

Thomas has since been playing at a fairly high-level. However, against the
Packers he was back to his old self. The Packers got anything and everything they wanted when they attacked Thomas. He simply didn't have it that game and it was clear that the lights were too bright for him. Now, it is just one game. Thomas hasn't looked anywhere close to that bad since he was made a starter. But it does make you wonder if the weight of the playoffs is unnerving for Thomas, which is concerning.

So, how concerned should the 49ers be with Thomas going into the NFC championship?

Very concerned. Usually I like to give players who have a bad game some slack when they have been playing well for a while like Thomas has. But he was getting beat by receivers who aren't the most threatening. Worst of all is that when he was in a position to make a play on a ball he couldn't do it. He committed a defensive pass interference when the opportunity was there for him.

Thomas looked to be in his head that game and I'm not too confident he can get out of it with a trip to the Super Bowl on the line. Kyle Shanahan was asked on a conference call on Monday about any concerns with Thomas and what the coaching points will be for him this week

“They're all different. You can't grab guys. So, it has to do sometimes with staying closer to them so you don't grab them when they make the second move," said Shanahan. "So, that could be one. The other one down the field, yes, that's not all on him. He needs a little bit more help and stuff. But in that down and distance, you’ve got to stay on top of that so you can flatten things when you're digging out from behind. Any balls under thrown like that, it's extremely, extremely hard to avoid the contact with the receiver going up for the ball. So he's got to make sure to get himself in better positions before he ends up in that tough position.”

All of these points are spot on from Shanahan. What he did wrong was fundamental and can be corrected, but when you are in a shaky mental state on edge you're going to make poor plays. I don't think the issues with Thomas are necessarily his play, but rather how nervous he is. It is kind of like when Ahkello Witherspoon was here. He was always playing his receivers well, but always struggled to make a play on the ball. That is due to a lack of confidence. Getting caught like a deer in headlights.

Hopefully Thomas got all of the nerves out of himself in the divisional round because the 49ers cannot afford him to be mediocre again. The Lions field a much stronger passing attack than the Packers and will easily take advantage of Thomas if he doesn't have it again. 

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