Nick Foles' consistent improvement exploded in a seven-touchdown performance against the Raiders. (Thearon W. Henderson/Getty Images)
Every year, players come out of nowhere to provide unexpected benefits to their teams. Here are some the most surprising players from the 2013 season.
Quarterback -- Nick Foles, Philadelphia Eagles
We'll give Houston's Case Keenum an honorable mention here, but really -- who else could it be? After his seven-touchdown performance against the Oakland Raiders, Foles has thrown 13 touchdown passes and no picks, all while working around a concussion and an uncertain quarterback situation. He currently ranks second in Football Outsiders' per-play metrics behind only Peyton Manning.
Running Backs -- Zac Stacy, St. Louis Rams/Giovani Bernard, Cincinnati Bengals
Bernard was the first back taken in the 2013 draft, a draft that saw no backs selected in the first round for the first time since 1963. He's looked every bit the first-round pick he wasn't though, giving the Bengals the kind of franchise player required in Jay Gruden's offense. Stacy, a fifth-round pick out of Vanderbilt, has amassed 261 rushing yards in the last two weeks after he was in a rotation through the first part of the season. Safe to say he's the Rams' main man at this point.
Receivers -- Marvin Jones, Cincinnati Bengals/Keenan Allen, San Diego Chargers/Alshon Jeffrey, Chicago Bears
Yes, Jones impressed with his four-touchdown performance against the New York Jets, but he's been effective all season when targeted. You don't become FO's most efficient play-to-play receiver with one great game. Allen overcame questions about his speed and injury situation to become a steal for the Chargers -- selected in the third round, he's become the team's number one receiver and caught eight passes for 128 yards in San Diego's overtime win over the Redskins last Sunday. Jeffery is on pace for more than 1,200 receiving yards in 2013 after an unimpressive rookie season. He's become the secondary target behind Brandon Marshall that the Bears desperately need.
Tight End -- Jordan Cameron, Cleveland Browns
Cameron caught a grand total of 26 passes in his first two NFL seasons, but he's already racked up 50 receptions for 600 yards and six touchdowns in 2013. There's little doubt that he's Cleveland's most productive and consistent receiver.
Tackles Cordy Glenn, Buffalo Bills/Austin Howard, New York Jets
Guards -- Kyle Long, Chicago Bears/Louis Vasquez, Denver Broncos
Center -- Dominic Raiola, Detroit Lions
Glenn didn't do a lot to impress in his rookie season of 2012, but he's allowed just one quarterback sack and three hits in 360 passing snaps. Similarly, Howard has taken advantage of an improved quarterback situation to allow just one quarterback takedown -- not bad for a guy who allowed 10 of them in 2012.
The Bears took Long in the first round this year, but some wondered if he was ready for prime time after just one season at Oregon. He's been an absolute rock as Chicago's right guard; perhaps the most consistent player on a line that swapped out four starters in the offseason. Vasquez may be the best pure pass-blocking guard in the league this year -- admittedly, it helps when Peyton Manning is your quarterback, but that shouldn't downgrade what Vasquez has done. And Raiola has completely reinvented himself in Detroit's upgraded offense -- when Reggie Bush gets the ball on a quick screen, you'll see the veteran blocking 20-30 yards upfield.
Defensive Tackles -- Jurrell Casey, Tennessee Titans/Dontari Poe, Kansas City Chiefs
Casey has been an absolute demolition machine in Tennessee's front four, with six sacks and 30 total quarterback pressures in just 254 passing snaps. And Poe has become a leader in the conversation for the Defensive Player of the Year award -- he's also played 582 snaps, by far the most of any defensive tackle (Dallas' Nick Hayden is second with 500).
Defensive Ends -- Rob Ninkovich, New England Patriots/LaMarr Houston, Oakland Raiders
Ninkovich has been a good pass-rusher in Bill Belichick's defense over the last few years, but what makes him a surprise player this season is his ability to stop the run. He's got 23 run stops this season, indicating that he's playing with above-average discipline for a player directed to penetrate the pocket more often than not. Houston is one of the most valuable hybrid ends in the league -- he can kick inside to tackle, but where he really excels is in bulling through blockers and making life difficult for quarterbacks. He has four sacks and 38 total pressures this season.
Linebackers -- Jerry Hughes, Buffalo Bills/Mike Neal, Green Bay Packers/Kiko Alonso, Buffalo Bills
Hughes was a draft bust with the Colts, but he's been highly effective in Mike Pettine's multiple fronts. As has Neal, who has taken some of the sting out of Clay Matthews' injury situation. As for Alonso, the second-round pick from Oregon is on track to become one of the league's best young defenders.
Cornerbacks -- Alterraun Verner, Tennessee Titans/Tyrann Mathieu, Arizona Cardinals
We've been talking about Verner all season, as have most who watch tape and pay attention to advanced stats. Any why not? No cornerback has allowed a lower opponent quarterback rating that his 23.2, and he's got four interceptions with no touchdowns allowed. Mathieu had a lot of people thinking he would never make in the NFL after missing the entire 2012 NCAA season following his dismissal from LSU for multiple drug offenses. He's become a great story and an entrant for Defensive Rookie of the year, excelling wherever the Cardinals put him on the field.
Safeties -- Tashaun Gipson, Cleveland Browns/Eric Reid, San Francisco 49ers
Gipson is primarily known as the defender who gave Green Bay Packers tight end Jermichael Finley his season-ending spinal injury, and that's unfortunate because he's been a pleasant surprise in coverage. Reid, meanwhile, has three picks and no touchdowns allowed in his rookie season.