 -- Time for a new Rookie Big Board, my ranking of the best rookies of the 2017 NFL season. Here's my top 30, plus where each player landed on my final top 300 prospects list before the 2017 draft.

Here are the parameters (same as always):

As with my other Big Boards, write-ups here won't change too much. I'll just note recent stat changes along with some of my scouting notes.

This is a measure for all games played this season -- not just last week.

Total snap count matters. Staying on the field is a measure of value.

Positional value matters, but overall performance and impact on the team matter more.

1. Alvin Kamara, RB, New Orleans Saints

Kamara played only a few plays on Thursday night before a helmet-to-helmet hit?sidelined him for the game, but he has been ridiculous since the Saints traded away running back? Adrian Peterson. His loss was felt against the Falcons. Kamara has 11 total touchdowns and leads the league in yards per carry (7.0) by more than a full yard. Kamara was my eighth-ranked running back before the draft, as he?split time in the Tennessee backfield and had only 210 carries?from 2015 to '16.?The Alabama transfer led all running backs with a 39?-inch vertical leap and 10-foot-11 broad jump at the combine.

2. Marshon Lattimore, CB, New Orleans Saints

Lattimore returned from an ankle injury on Thursday night -- he had missed the previous two games -- and added another interception. He has been one of the best cornerbacks in the league?overall. He has three interceptions (one for a touchdown), 10 pass breakups, 39 tackles and a forced fumble, and he has been a huge part of the Saints' defensive improvement. New Orleans' 2017 draft class looks really solid. Lattimore is a ridiculous athlete. He ran a 4.36-second 40-yard dash and had a 38?-inch vertical and 11-foot broad jump at the combine. He also has a high ceiling. Remember: He started only one season at Ohio State.

3. Tre'Davious White, CB, Buffalo Bills

Like Lattimore, White has had a fantastic season. White's 15 pass breakups are tied for?third in the league. He also has three interceptions, a forced fumble,?46 tackles and a fumble return for a touchdown. A four-year starter at LSU who had six career interceptions, White was one of the most consistent prospects I graded in the Class of 2017. He became Buffalo's No. 1 corner after? Ronald Darby?was traded to the Eagles.

4. Kareem Hunt, RB, Kansas City Chiefs

Hunt's touchdown-less slump has reached a whopping nine games. He's averaging just 3.4 yards per carry in those six games. He still ranks third overall in rushing yards over the season (930), and he has?six total touchdowns. The Chiefs have lost six of seven, and the offense has struggled. But Hunt is still in the Rookie of the Year race.

5.? Ryan Ramczyk, OT, New Orleans Saints

This makes?three Saints rookies in my top five. It's one of the best rookie classes in a long time. Ramczyk got my midseason offensive lineman of the year?award. He started at left tackle for a few games in place of Terron Armstead and lately has played on?the right side in place of injured Zach Strief. I thought he might be better as a right tackle in the NFL because of his run blocking, and Armstead, who is signed through 2021, is locked into the left tackle spot, barring injury.

6. Myles Garrett, DE, Cleveland Browns

Garrett has played in only seven games due to injuries, but it's clear why he was the No. 1 prospect. He has five sacks and 15 total quarterback knockdowns, and he has the look of a future All-Pro pass-rusher. The No. 1 overall pick is a bright spot for the winless Browns, who?just fired the general manager who picked him. Garrett is an athletic specimen (4.64-second 40-yard dash and 41-inch vertical at 6-foot-4, 272 pounds at the combine) who spent the entire 2016 season atop my Big Board. He was the top pass-rusher in a really good class of them; he had 32.5 sacks in his three seasons at Texas A&M.

7. Carl Lawson, DE, Cincinnati Bengals

The fourth-round pick is playing only part-time in the Bengals' pass-rushing rotation -- he has played 41.6 percent of defensive snaps so far -- but he's up to 7.5 sacks and 19 quarterback knockdowns. A former five-star recruit, he missed a season and a half at Auburn because of injuries and returned as a senior in 2016 with nine sacks and 12 tackles for loss. He could be a 10 sack-a-season guy if he stays healthy (which includes taking better care of his teeth).

8.? Christian McCaffrey, RB,? Carolina Panthers

McCaffrey had a tough time getting yards on the ground early in the season, but he is averaging 5.1 yards per carry in his past four games. He's still at only 3.5 yards per carry overall, but he has been better. And he has 64 total catches for 501 yards and four touchdowns, so the Panthers are using him all over the field. He led the nation in all-purpose yards per game with 211.6 last season at Stanford, and he can be a weapon. I called him one of the safest picks in the draft, and I like his long-term future. He's a versatile weapon who will help Cam Newton for years to come.

9.? Reuben Foster, LB, San Francisco 49ers

Foster has 37 tackles over his past four games after missing most of the rest of the season through injury. He also has five tackles for loss on the season. He was one of my favorite 2017 prospects and my top-ranked inside linebacker. He's the reason the 49ers parted ways with longtime stalwart NaVorro Bowman earlier this season. I thought Foster might be picked in the middle of the first round -- I projected him to the Colts at No. 15 in my two-round mock -- but he dropped to No. 31 overall, in part because of some off-field concerns. He has a chance to be one of the steals of the early rounds.

10. T.J. Watt, OLB, Pittsburgh Steelers

The younger Watt brother had a dynamic debut with?two sacks and an interception against the Browns in Week 1. He missed most of the Steelers' Week 2 victory over the Vikings and all of the Week 3 loss to the Bears, but he has been disruptive in the Steelers' rotation since. He has five total sacks. I noted before the draft that Watt likely would start out as a situational pass-rusher in a 3-4 defense, but?it has been tough to keep him off the field. He has 36 total tackles.

11. Desmond King, CB, Los Angeles Chargers

The fifth-round pick has been the Chargers' primary slot corner this season, and he has made an impact. He has three sacks, five total tackles for loss, an interception?return for a touchdown and 42 tackles. The 5-10, 200-pound King isn't very big nor super fast, but he had 14 career interceptions at Iowa and?won the?Jim Thorpe Award in 2015. I thought he might have to move to free safety, but he has found a home in the slot.

12. Zach Cunningham, ILB, Houston Texans

The second-round pick has played more than expected after Brian Cushing's suspension. He has 47 total tackles and added his first sack of his career in last Sunday's loss to the Titans. At 6-3, 230, he's tall for an inside linebacker, but he has the athleticism to cover tight ends and can help in nickel and dime situations. He has a high ceiling.

13. Dalvin Tomlinson, DT, New York Giants

Tomlinson has started all 12 games for the Giants and played 52.9 percent of the defensive snaps. He has 37 tackles and a sack. At 6-3, 317, he's not a great pass-rusher, but he's more than a plugger. The second-round pick can get into the backfield.

14.? Jamal Adams, S, New York Jets

The Jets' rookie safety duo of Adams and Marcus Maye has been solid but unspectacular. Adams has 52 total tackles, two sacks, seven tackles for loss and has recovered two fumbles while playing almost every snap on defense. He's a stud.?Adams, my No. 1-ranked safety before the draft, can play in the box and help out on blitzes, and he can cover tight ends and slot receivers.

15. Cooper Kupp, WR, Los Angeles Rams

Kupp has 51 catches for 665 yards and three touchdowns while playing the slot for the Rams. He has played almost 74 percent of the offensive snaps so far. Kupp was one of the most physically ready receivers in the 2017 draft. He had an NFL skill set in the slot coming out of Eastern Washington, where he had 428 catches and a whopping 73 receiving touchdowns in his college career.

Best of the rest

17. John Johnson III, S, Los Angeles Rams:?The former Boston College safety has 44 tackles and an interception in eight starts.

18. JuJu Smith-Schuster, WR, Pittsburgh Steelers:?He has?five touchdowns while taking on a bigger role for the Steelers.

19. Pat Elflein, C, Minnesota Vikings:?The former four-year starter at Ohio State has played almost every snap.

20. Takkarist McKinley, DE, Atlanta Falcons:?McKinley has five sacks and nine total quarterback knockdowns.

21. Leonard Fournette, RB, Jacksonville Jaguars:?The former LSU star has cooled off a bit lately, but he's still seventh in the league in rushing yards (822) and has eight total touchdowns.

22. Jarrad Davis, LB, Detroit Lions:? Davis has 64 total tackles, a sack and an interception in 10 starts.

23. Marcus Maye, S, New York Jets: The second-round pick has 61 total tackles, two interceptions and a forced fumble.

24. Derek Barnett, DE, Philadelphia Eagles: ?Barnett has?five sacks, 16 quarterback knockdowns and a fumble recovery while playing in the Eagles' pass-rushing rotation.

25. Solomon Thomas, DE, San Francisco 49ers:? Thomas has eight tackles for loss, two sacks and 10 total quarterback knockdowns.

26. Kendell Beckwith, LB, Tampa Bay Buccaneers: The third-round pick has 57 tackles, a sack and a forced fumble.

27. Adoree' Jackson, CB, Tennessee Titans: The first-round pick has started all 12 games and has broken up 12 passes but doesn't have an interception.

28. Marcus Williams, S, New Orleans Saints: Williams has 52 tackles and two interceptions for an improved Saints defense.

29. Eddie Jackson, S, Chicago Bears:? The fourth-round pick has started every game for the Bears and had 75-yard-plus touchdowns (one interception, one fumble return) in Week 7. He has 43 total tackles.

30. Evan Engram, TE, New York Giants: Engram is being used like a receiver -- he hasn't been asked to block a whole lot. He has 51 catches for 569 yards and six touchdowns.