Welcome to Around The NFL's "Rookie Watch" series, a week-by-week journey ranking this year's promising collection of first-year players.
Between now and the end of the regular season, we'll chart this year's rookie class in an effort to predict which young players have the best chance at long careers in our nation's finest sport.
Now it's time to look at rookie workloads. Using snap counts provided by Pro Football Focus, the following is an assortment of draftees who have lived up to the billing, outplayed expectations and failed to get on the field:
The war daddies
Nobody in the league has played more snaps than Bitonio, Cleveland's mauling guard who ranks behind only Marshal Yanda at his position, per PFF. Had center Alex Mack stayed healthy alongside Bitonio and Joe Thomas, it's possible the Browns could have sent three O-linemen to the Pro Bowl. ... Martin feels like an all-star game shoo-in after anchoring the league's youngest and fiercest front five in Dallas. Like Bitonio, he hasn't missed a snap all year.
Right tackle Seantrel Henderson deserves credit for playing from wire to wire. He's struggled both as a run-blocker and pass-protector, though, with only Anthony Collins and Gosder Cherilus allowing more quarterback hits on the year at their position. ... The Seahawks have leaned on Britt from Day 1 to take over for the departed Breno Giacomini and Michael Bowie at right tackle. Calling Britt a "Wally Pipp story," coach Pete Carroll said last month: "He's studied like crazy, he's taken the responsibility to heart, he's fit in beautifully with our guys and he's played really good football."
Of this year's potentially historic crop of rookie wideouts, nobody's played more snaps than Watkins. The Bills playmaker has been streaky, though, following back-to-back 100-yard outbursts in Weeks 7 and 8 with 27, 32, 35 and 11 yards over his past four starts.
No first-year receiver has been better of late than Beckham, averaging 7.6 catches and 118.6 yards per outing since Week 9. His earth-rattling catch against the Cowboys two Sundays ago might have put him over the top for Offensive Rookie of the Year -- an astounding feat for someone who missed the first month of the season.
The running back class hasn't been especially potent, but gems exist. I'm impressed with Hill, who capably stepped into a lead role with the Bengals between Weeks 9 and 11 to average 120 yards per start. Advertised as a hammer-dropping inside runner, Hill has been much more with his ability to hit the edge and gain extra yardage with his quick cuts. His workload has been nearly equal to Giovani Bernard's 407 snaps.
Mason didn't earn his first start until Week 9, but he's fit in well with the St. Louis offense since. His 164 total yards and two touchdowns against the Raiderson Sunday were the product of his sneaky breakaway speed and dangerous pass-catching ability out of the backfield. Play-caller Brian Schottenheimer deserves credit for feeding Mason the ball and upping his snaps over the past month-plus.
Promise on the inside
Mosley has been on our radar since August as a potential Defensive Rookie of the Year candidate at the inside linebacker spot. Leading the Ravens and all fellow rookies with 71 tackles, the former Alabama star trails only Bitonio in snaps played among draftees. Seeing more work as a pass rusher in recent weeks, Mosley is arguably this season's most complete first-year defender.
Borland, though, has dazzled of late, piling up an outrageous 54 of his 69 tackles since Week 9. He ranks second among all rookies in that category behind Mosley despite 430 fewer snaps than the Ravens linebacker.
Mixed bag at cornerback
How many of you had sixth-rounder E.J. Gaines penciled in as a top-three cover man? We mentioned in Sunday's romp over the Raiders how active Gaines was in the secondary, playing every snap and seeing far more time than Janoris Jenkins or Trumaine Johnson. Listed as one of our late-round steals, Gaines plays inside and out and has emerged as the team's fourth-highest-ranked defender, per PFF.
Not the case with Gilbert, who lost his starting job early in the year to fellow rookie K'Waun Williams and remains on the outside looking in for serious playing time. Averaging just 13 snaps per tilt over his past three starts, Gilbert has yet to live up to his first-round pedigree.
Seeing his snaps grow weekly, Donald has cemented himself as a run-stopping force for the Rams. His six sacks are tied for fourth among all defensive tackles and more than first-rounders Khalil Mack, Dee Ford and Mosley combined. He's got plenty of competition for Defensive Rookie of the Year, but Donald looks like a long-term fixture ready to wreak havoc in the NFC West.
Workload on the rise?
Coach Mike Pettine and general manager Ray Farmer must find a way to evaluate their first-round pick, who came off the bench to play a season-high 13 snaps against the Bills. Farmer called that performance "very impressive" after telling reporters last month that the organization's goal is to help Manziel succeed "for an extended period of time," adding: "He's going to be ready, and we're going to be ready when he does get that opportunity."