Mel Kiper Jr. 2018 Big Board: Sam Darnold, Josh Rosen Top Latest Rankings

The 2017 college and NFL seasons have just started, but it's not too early to look ahead to the riches in the upcoming draft class.

ESPN NFL draft guru Mel Kiper Jr. released his updated big board that features 25 players for the 2018 NFL draft Thursday, and quarterbacks Sam Darnold from USC, Josh Rosen from UCLA and Josh Allen from Wyoming occupy the top three spots.

With quarterback-needy teams like the New York Jets and San Francisco 49ers likely to be picking near the top of next year's draft, having multiple players at the position to choose from is good news for them.

Here's a closer look at the most notable players on Kiper's current big board.

Sam Darnold, USC, QB (Kiper Rank: No. 1)

Jae C. Hong/Associated Press

Through the first two games of USC's season, Darnold has been more hit-and-miss than his big-board ranking would suggest.

The sophomore is completing passes at a terrific 74.6 percent rate with 605 passing yards, but he's thrown as many interceptions (four) as touchdowns (four) and didn't have a touchdown pass in the season opener against Western Michigan.

Kiper addressed Darnold's turnovers and his throwing motion in his analysis of the USC star.

"Darnold has thrown too many interceptions to start the 2017 season—four in two games—and he has an unorthodox, long delivery that will have to be tweaked," Kiper wrote. "But the third-year sophomore is an exciting prospect who could go No. 1 overall in next April's draft."

Turnovers were also part of Darnold's game during his breakout 2016 season. Eight of his nine interceptions last season came in the 10 games he started, including a four-game stretch from Oct. 27-Nov. 19 in which he threw six picks.

Darnold's propensity for turnovers bears some resemblance to what Jameis Winston did at Florida State. Winston was picked off 28 times in two seasons, including 18 the season before the Tampa Bay Buccaneers drafted him first overall.

Despite some interception and mechanical concerns, Darnold looks the part of an NFL quarterback at 6'4" and 220 pounds, per USC's athletics website. He entered the year as the quarterback to beat for the No. 1 spot and thus far hasn't relinquished his throne.

Josh Rosen, UCLA, QB (Kiper Rank: No. 2)

Alex Gallardo/Associated Press

It's only two games, but Rosen appears to have taken a significant leap in his development two years after being anointed as a perfect NFL prospect as a true freshman.

The UCLA junior is completing a career-high 67.9 percent of his passes, averaging a career-best 9.76 yards per attempt, and he has nearly matched his passing touchdown total from last season (10) with nine scores.

A shoulder injury limited Rosen to six games last season, so fans and analysts are seeing what he's capable of at full strength.

One NFL personnel man did offer some criticism of Rosen to Sports Illustrated's Bruce Feldman after UCLA's historic 45-44 win over Texas A&M on Sept. 3 in which the Bruins erased a 34-point third-quarter deficit:

“You have to have some luck, and he definitely got away with a number of poor choices. However, he can stand in the pocket and deliver the football with different arm angles and off platform. The question is from the neck up, he’s got everything from the neck down. Plenty of arm, easy release, accuracy when moving from one receiver to the next."

Rosen made headlines in August for telling B/R's Matt Hayes that "no one in their right mind should have a football player's schedule and go to school."

There's ample evidence Rosen is going to say whatever is on his mind, which can rub NFL teams the wrong way because a quarterback has to be the face of a franchise and keep things on an even keel in good and bad times.

If Rosen continues to play at a high level, his direct manner of speaking won't matter to teams in search of a franchise quarterback.

Lamar Jackson, Louisville, QB (Kiper Rank: No. 13)

Gerry Broome/Associated Press

Sticking at quarterback, reigning Heisman winner Lamar Jackson has received a huge bump through two games this season.

After not making Kiper's initial top 25 on Aug. 31, Jackson has shot up the rankings as the No. 4 quarterback and No. 13 prospect overall.

Kiper's reasoning for bumping Jackson up is related to specific improvements in his game as a passer and slight differences in his body:

"Well, it's early, but his start to the season has been promising. Jackson's completion percentage is way up (64.7 from 56.2 in 2016), he has put on some good weight and his delivery looks more fluid. And he has done all of that while retaining his dynamic athleticism and speed. The matchup versus Clemson this weekend is important because the Cardinals' schedule gets easier afterward. Jackson will have NFL prospects chasing after him all game."

Listed at 6'3" and 211 pounds by ESPN.com, Jackson isn't small by normal standards, but Albert Breer of The MMQB did note Jackson's frame doesn't look like that of a traditional NFL quarterback.

"He's listed at 6'3" and 212 pounds, but looks a little shorter and lighter than that, and is built more like a basketball player than a football player, with a frame that may not lend itself to getting much bigger," Breer wrote.

By size and weight, Jackson's frame is nearly identical to Minnesota Vikings quarterback—and former Louisville standout—Teddy Bridgewater (6'2" and 215 pounds, per NFL.com).

One AFC scouting director told Breer in 2014 that Bridgewater's body type was a "concern" because he "looks small and skinny."

Bridgewater looked like he was on a path to becoming a very good quarterback with 6,150 yards, 28 touchdowns, 21 interceptions and a completion percentage of 64.9 in 29 NFL games before a non-contact knee injury sustained during an Aug. 2016 practice led to concerns about his playing future.

If Jackson is able to continue his ascent as a pocket passer and remain a dynamic runner, he will continue to move up draft boards because of his unique playmaking skills at the most important position on the field.

Derwin James, Florida State, S (Kiper Rank: No. 5)

Kevin C. Cox/Getty Images

Offense dominates the top of Kiper's big board, but Florida State safety Derwin James breaks through for players on the other side of the ball at No. 5 overall.

James' on-field showing this season has been limited to one game because the state of Florida is still trying to piece things together after Hurricane Irma. The Seminoles canceled last week's game against Louisiana Monroe and postponed this week's game against Miami.

The only game Florida State has been able to play this season was a 24-7 loss to Alabama in the season opener. James was a playmaking machine for the Seminoles in that game with six total tackles and half a sack.

The sophomore picked up where he left off in his breakout 2015 season when he recorded 9.5 tackles for loss and 4.5 sacks in 12 games.

James was limited to two games in 2016 after undergoing surgery to repair a torn meniscus in his left knee. Seeing him back on the field and healthy is a positive sign for his draft stock.

NFL.com's Chase Goodbread broke down some of the numbers that make James such an appealing prospect to all 32 NFL teams:

"James is a chiseled 6'3" and 215 pounds, with strength and explosiveness that set him apart even in one of the most talented locker rooms in the country. He can bench-press 450 pounds, and he's approached 600 on the squat rack. He's broad-jumped 11 feet, 3 inches, which would have ranked him in the top five among more than 300 players at the 2017 NFL Scouting Combine. You want speed? He was clocked at 4.49 seconds in the 40-yard dash at the Nike Opening coming out of high school."

With a unique combination of size, speed and strength, James has the ability to play multiple positions on defense. He's fast enough to line up at cornerback, strong enough to play on the line or at linebacker, and rangy enough to protect against big plays down the field as a safety.

NFL teams continue to look for versatility on both sides of the ball, and James is a perfect prospect as the sport moves into the future.