Every Tuesday, PFF will be releasing its Team of the Week, representing the highest-graded players at each NFL position for that week. But Senior Analyst Sam Monson gets a jump on that by picking out the 10 least-impressive individual performances from Sunday’s games.

Here are the 10 worst players from Sunday’s Week 12 action:

[Check out the 10 best performances from Sunday of Week 12 right here, or access our Player Grades tool to see how every NFL player measures up through three weeks of the season.]

1. Jonathan Casillas, LB, New York Giants

Linebacker seems like a perennial problem position for the New York Giants, and even this season they seem to rotate which player puts up a truly awful performance week to week. This week it was Casillas’ turn, as he was exposed against both the run and pass. He missed a pair of tackles and was beaten for 61 yards through the air, with more than half of them coming after the catch, despite the Browns struggling hugely on offense. As the playmaking linebacker in New York’s 4-3 defense, Casillas managed just one solitary defensive stop in the game over 45 snaps of action.

2. Bryce Callahan, CB, Chicago Bears

There were cornerbacks this week with worse stats than Callahan, but probably none with a worse performance overall that could have looked so much worse statistically. Tennessee QB Marcus Mariota missed his intended receiver deep on a double move in the third quarter with Callahan well beaten that could have made the numbers against him look much worse, and Callahan also had a holding penalty on WR Tajae Sharpe. Overall, Callahan surrendered only 60 receiving yards, but his game was littered with mistakes and bad plays, several of which didn’t show up in his stat sheet.

3. Germain Ifedi, G, Seattle Seahawks

Russell Wilson was under pressure on 23 of his 45 dropbacks against Tampa Bay, and Ifedi was responsible for seven of those pressures, including three sacks. Ifedi was effectively destroyed largely by Tampa Bay’s Gerald McCoy on the inside, including on key downs late in the game when the Seahawks were desperately trying to claw their way back into the game. Ifedi had the kind of performance that makes a team’s chances of winning the game shrink dramatically.

4. Mitchell Schwartz, T, Kansas City Chiefs

Schwartz owes a lot of his reputation to the job he did shutting down Von Miller a year ago, for the Browns, but playing at less than 100 percent this week he wasn’t close to the same kind of display. Schwartz allowed a pair of sacks and three more hurries on 58 snaps of pass-blocking action, but also struggled in the run game and looked nothing like his best going up against one of the league’s most dominant edge defenders. Alex Smith was under pressure 17 times in the game, and Schwartz was at fault for five of them.

5. Ty Sambrailo, T, Denver Broncos

Denver’s revolving door at right tackle continues, with both Sambrailo and Donald Stephenson being given just enough playing time until the team feels the need to pull them from the game because it can’t possibly get any worse, only to do the same thing again and simply alternate between problem players. In just 20 snaps before being sat down, Sambrailo coughed up a pair of sacks and a hurry as well as a penalty for holding. What’s worse is that every time he was beaten, he was beaten badly and quickly, giving his QB little chance on the play.

6. Russell Wilson, QB, Seattle Seahawks

Wilson has been excellent this season at less than full health and dealing with an offensive line that seems intent on making his life as hard as humanly possible, but the wheels came off that wagon this week and for whatever reason he was just not able to function as he has the rest of the year. Wilson threw two interceptions but also lost the ball on a fumble and threw another pass to Bucs CB Brent Grimes that should have been picked off as well. About the only positive in his game was rushing the ball, where he picked up 80 yards on eight carries.

7. Cameron Meredith, WR, Chicago Bears

For some reason the Chicago receivers this week couldn’t catch the football. The team combined for 10 dropped passes, which is the most by any team in a single game over the 10 years of PFF grading. They collectively conspired to make Matt Barkley’s stats look incredibly average, whereas he was far better than that in the game. Meredith was thrown at nine times, dropping more passes (three) than he caught (two), and notching just 19 yards on the day.

8. Josh Bellamy, WR, Chicago Bears

Meredith wasn’t alone, and teammate Bellamy also dropped three passes on nine targets. Bellamy did at least catch more (four) than he dropped, and ended the game with 41 receiving yards, but those drops were a huge factor in deciding the outcome of this game, and left several plays out on the field that the Bears just weren’t in a position to turn down.

9. Ulrick John, T, Arizona Cardinals

There is a dearth of quality starting tackles in today’s NFL, so when you are forced to go to the bullpen, things typically get pretty ugly pretty quickly. Arizona started John at right tackle against the Falcons and he made Vic Beasley look like Reggie White. John allowed a sack, a hit and seven hurries over the course of 51 pass-blocking snaps, putting Carson Palmer under pressure nine times, or more than half of the total snaps he was pressured in the game.

10. Josh McCown, QB, Cleveland Browns

It looks harsh to criticize McCown’s performance given he was sacked seven times against the Giants, because that suggests the kind of unmanageable pressure that QBs just can’t play against. He was actually at fault for more of the sacks than any other individual player (two) and the architect of much of his own woe by holding the ball too long and making life more difficult for his pass protection as he tried to find somewhere to go with the ball. McCown ended up throwing for 322 yards, but completed just 58.1 percent of his passes, and his passer rating when under pressure was only 48.6.