Carr, Nelson among 2017's most disappointing players

As the 2017 regular season winds down, it's a great time to single out a few players who didn't live up to expectations this year. Obviously, this list could be extremely long, but we narrowed it down to just five in alphabetical order. Rookies have been excluded from the conversation.

QB Derek Carr, Oakland Raiders

The Raiders' offense has taken a huge step backward this year, and it's fair to question the coaching and overall approach. Carr also injured his back early in the season and it's reasonable to wonder if that's bothered him all year.

Still, he certainly hasn't taken the expected step forward this year. Carr is getting the ball out very quick - which isn’t uncommon for him - but it means he's rarely threatening defenses downfield even though the Raiders have an excellent offensive line. And not only is Carr rarely making (or attempting) difficult throws, but he's also putting the ball in harm’s way far too often.

The biggest concern with Carr coming out of college was his ability to handle pressure, and maybe most concerning of all, he looks to have taken a step backward in that crucial area of quarterbacking. It's too soon and there are too many other factors at play to question if Oakland made a bad decision by giving Carr a massive long-term deal, but there's no denying the early returns are worrisome.

WR Amari Cooper, Oakland Raiders

Not to pick on the Raiders, but Cooper takes the cake here.

There's no denying his great ability, as we've seen this 23-year-old play at a very high level for much of his career. He's what you look for in a true No. 1 receiver, but drops have plagued him since joining the league and he also has a history of slowing down late in the year while lacking big touchdown numbers.

The drops have been a huge problem for Cooper again this season. And while the Raiders' offensive scheme hasn't helped, teammate Michael Crabtree is producing, isn’t he? Other than a 210-yard, two-touchdown performance against the Chiefs, we haven't seen nearly enough from Cooper.

To be fair, Cooper hasn't been healthy of late, but the 62 yards he amassed in Week 1 was his next-best performance. In fact, he has five games this year with 10 receiving yards or fewer! Here we sit a few days before Christmas, and he's still short of 500 for the season. No one saw that coming.

LB Dee Ford, Kansas City Chiefs

After notching 10 sacks last season, many thought Ford had arrived and would live up to his first-round selection from 2014.

Instead, he hasn't played well against the pass or run this season. Ford has just two sacks and also doesn’t set the edge well against opposing backs. That's partly because he isn’t a thickly built player and lacks power at the point of attack. His game is much more finesse than brute force, but he isn’t an extreme athlete for the position, and that goes for his pure speed and initial quickness as well.

Staying healthy has also been a problem, which has been the case again this year. Even with Justin Houston and Tamba Hali on board, the Chiefs need much more from Ford than what they've gotten in 2017.

CB Kevin Johnson, Houston Texans

With Kareem Jackson and Johnathan Joseph already on board, the Texans looked as though they had an embarrassment of riches at the cornerback position after selecting Johnson in the first round of the 2015 draft. Although lean, Johnson has very good height and length, fluid movements, and loose hips - traits that made him look like an ideal prospect for man-to-man coverage in the NFL.

However, injuries have been a problem for Johnson since entering the league, and he lacks the necessary physicality for the position at this level. He's been picked on all season and has yet to really have a standout performance in 2017.

Compounding matters, Jackson and Joseph have also been very underwhelming. Sure, losing Whitney Mercilus and J.J. Watt has hurt Houston’s pass coverage in a big way, but this secondary has performed like one of the worst in the NFL this year. Let's just say Johnson is fortunate that Antonio Brown won’t be playing on Christmas.

WR Jordy Nelson, Green Bay Packers

Nelson has been without his main man, Aaron Rodgers, for a large portion of the season. But the unfortunate fact is that Nelson also looks done. He'll turn 33 this offseason and is going through a downright awful campaign.

Nelson has exceeded 50 receiving yards just four times - most recently in the middle of October. Since then, he's averaged under 23 receiving yards across his last eight games. Once a big-play threat, Nelson is also averaging just 9.4 yards per reception this season. Even when Rodgers returned last week, Nelson mustered only three catches for 28 yards, so we can’t just blame Brett Hundley for the massive lack of production.

Davante Adams is now Green Bay's No. 1 wide receiver, but is a free agent after the season. He'll also be sidelined in Week 16, which means Nelson should see a lot of Minnesota's Xavier Rhodes. The Nelson of the last few years would be up for such a huge challenge. That isn’t the case anymore.

Matt Williamson is a former scout for the Cleveland Browns and spent 10 years at ESPN as a scout and co-host of "The Football Today Podcast." Find him on Twitter @WilliamsonNFL.

(Photos courtesy: Getty Images)