NFL players are aware when they do not perform up to expectations. 

Following a disappointing 35-17 loss to the Green Bay Packers, the Detroit Lions' defense is reeling. 

Two position groups on the 2021 defense -- linebackers and cornerbacks --  have seen subpar performances to start the season, and it doesn't appear that much can be done to improve their current plight. 

On Tuesday, head coach Dan Campbell pointed out that veteran linebacker Jamie Collins did not perform well in front of a nationally televised audience. 

"Jamie, look, Jamie had some mistakes. It wasn’t certainly his best performance," Campbell said. 

Amid growing concerns regarding the veteran's effort level, Campbell was asked directly if those concerns were warranted. 

"Jamie’s a big linebacker. He’s a very athletic linebacker. And the way he moves is a little bit different. Now, does he move with the same effort and have the same effort as Alex (Anzalone)? No, I don’t think so," Campbell said. "I think Alex just plays at a high level all the time. That’s him, that’s how he goes. But Jamie, there’s things that Jamie does well that we still have to continue to use. He’s still a mismatch on third down, particularly in the rush game. We’ll see where this goes."

Is another team willing to take on Collins' hefty salary? Would they be willing to offer general manager Brad Holmes a late round pick for him based on the growing question marks regarding his effort level?

At this point, that notion is highly unlikely, given his play during his tenure with the Lions. 

Holmes and Co. will have a key decision to make following the 2021 season regarding Collins' future. 

Back in 2020, the 31-year-old signed a three-year, $30 million deal with Detroit that included $18 million in fully guaranteed money. 

He carries with him a $13.3 million cap hit in 2022 and a dead money cap hit of $6.3 million.  

Meanwhile, Alex Anzalone is playing on a one-year contract and will become an unrestricted free agent following the conclusion of the 2021 season. 

"Alex wasn’t perfect but I thought he was all over the field and made a lot plays. I thought he played with a lot of energy, I think he was spot on with his calls, and look, he’s high effort," Campbell said. "He’s smart, he’s kind if what we’re about here, and so I like him where he was at."

Based on the early start to his 2021 season, Collins role will be reduced to make way for the emerging Derrick Barnes, who is likely going to see the field significantly more against the Baltimore Ravens at Ford Field

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