Of the top 25 running backs in the class of 2017, six are on their way to the SEC this fall.

Five-star RB Najee Harris, already enrolled at Alabama, headlines the SEC’s latest haul. While the Crimson Tide had a formidable backfield in Damien Harris and Bo Scarbrough, Harris has the potential to become a No. 1 running back, something scary for SEC defenses.

Tuscaloosa’s own Brian Robinson, a 4-star signee, wasn’t scared off by Harris being in the class.

RELATED: 3 reasons Najee Harris might be the best RB Nick Saban has ever recruited

Georgia’s backfield is already overflowing with talent, but Kirby Smart knows UGA’s future is bright with 4-star D’Andre Swift on the way. He and 2016 signee Elijah Holyfield will likely be the team’s top two backs in 2018.

The departures of Jalen Hurd (transfer) and Alvin Kamara Jr. (NFL) made Tennessee determined to find a 2017 running back ready to step in this fall and complement John Kelly. The Volunteers think they’ve found just that in 4-star RB Ty Chandler out of Nashville.

With five running backs already on roster, Auburn’s Devan Barrett might not see many carries in 2017, but the Tigers’ depth at the position is a valuable asset for the long-term.

The state of Mississippi produced two blue-chip running backs this recruiting class, but only one, 4-star Columbus product Kylin Hill, will be playing in the SEC. Mississippi State coach Dan Mullen wisely focused on Hill early while Ole Miss went all in on 5-star Clinton product Cam Akers, who signed with FSU.

Star ratings and high school highlights don’t always mean everything. Just look at the 2016 class, which saw three unheralded recruits each become a 1,000-yard rookie rusher.

Here’s how the SEC’s past five running back classes rank, potentially offering some insight into 2017:

1. 2013

5-stars: 2
4-stars: 11
3-stars: 11

Of the past five classes of SEC running backs, there’s only one Heisman Trophy winner: Alabama’s Derrick Henry. At 6-3, 240 pounds, some coaches saw Henry as a potential linebacker, and he was classified as an athlete in recruiting rankings, indicating he could play on either side of the ball.

It’s safe to say Alabama coach Nick Saban made the right call letting Henry line up in UA’s backfield, as he carried the Crimson Tide to a 2015 national championship by powering his way through SEC defenses.

The other 5-star signee of this class, Florida’s Kelvin Taylor, didn’t live up to the hype (though he ended his career with a 1,000-yard season), but there was still more to the class than just Henry.

Alex Collins (Arkansas) and Cameron Artis-Payne (Auburn) are both in the NFL after making their mark in the SEC, and Kamara (originally an Alabama signee in 2013) is looking to join them in the league in 2017. Ralph Webb had the lowest position ranking (No. 77 running back) of the SEC signees, but he has exceeded all expectations at Vanderbilt and become one of the SEC’s top ball-carriers.

2. 2014

5-stars: 5
4-stars: 5
3-stars: 10

On paper, this should be the top class. Four of the top five running backs – Leonard Fournette (No. 1, LSU), Roc Thomas (No. 3, Auburn), Sony Michel (No. 4, Georgia) and Nick Chubb (No. 5, Georgia) – all signed with SEC schools. This could have been five-for-five had FSU’s Dalvin Cook stuck with his Florida pledge. This class also had Alabama’s Bo Scarbrough as the No. 2 athlete of the class, a 5-star recruit.

Nov 5, 2016; Baton Rouge, LA, USA; LSU Tigers running back Leonard Fournette (7) before a game against the Alabama Crimson Tide at Tiger Stadium. Mandatory Credit: Derick E. Hingle-USA TODAY Sports

Credit: Derick E. Hingle-USA TODAY Sports

The star power is there, and Fournette had an incredible career when healthy, but not many of these careers have gone as planned. The 2016 season was supposed to be the year of Fournette and Chubb, but they were injured and upstaged by lesser-known SEC ball-carriers. Thomas transferred out of Auburn, (luckily the Tigers also signed Kamryn Pettway). Jalen Hurd has left Tennessee. Scarbrough was limited by injuries this season.

This class has the potential to establish a lasting legacy and take the No. 1 spot, but it needs a big finish.

3. 2012

5-stars: 3
4-stars: 9
3-stars: 7

The oldest class benefits from having the longest resumes. Only one of the 5-stars, Alabama’s T.J. Yeldon, really made a splash in college. Texas A&M’s Trey Williams bounced around the NFL in 2015 after leaving early and Georgia’s Keith Marshall is currently on the Washington Redskins’ roster.

The standout of the class is undoubtedly Todd Gurley, the lower-rated recruit (No. 7 running back, 4-stars) of Georgia’s two running back signees.

Jan 1, 2017; Los Angeles, CA, USA; Los Angeles Rams running back Todd Gurley (30) in action against the Arizona Cardinals during the second quarter at Los Angeles Memorial Coliseum. Mandatory Credit: Kelvin Kuo-USA TODAY Sports

Credit: Kelvin Kuo-USA TODAY Sports

Gurley, a first-round pick of the Rams, was NFL Offensive Rookie of the Year in 2015 and also made the Pro Bowl. Other NFL backs from the class of 2012 include Kenyon Drake (Alabama), Matt Jones (Florida) and Jonathan Williams (Arkansas).

4. 2016

5-stars: 0
4-stars: 12
3-stars: 12

Opposite of 2014, the 2016 group is the class most lacking star power. It’s also a reminder that the recruiting rankings don’t always get it.

This season, three freshmen – Texas A&M’s Trayveon Williams (pictured), Missouri’s Damarea Crockett and Kentucky’s Benny Snell – all cracked the 1,000-yard rushing mark, a first in conference history for three rookie running backs.

Oct 8, 2016; College Station, TX, USA; Texas A&M Aggies running back Trayveon Williams (5) in action during the game against the Tennessee Volunteers at Kyle Field. The Aggies defeat the Volunteers 45-38 in overtime. Mandatory Credit: Jerome Miron-USA TODAY Sports

Credit: Jerome Miron-USA TODAY Sports

Williams was a top-10 all-purpose back (No. 8), but Crockett (No. 30 running back) and Snell (No. 56 running back) were under-the-radar recruits. Arkansas’ Devwah Whaley only logged 602 rushing yards this season, but looks like a future 1,000-yard rusher.

This group should be fun to watch in the coming years and climb the rankings over time.

5. 2015

5-stars: 1
4-stars: 14
3-stars: 13

There’s a case that the stars of the 2015 class – LSU’s Derrius Guice, Arkansas’ Rawleigh Williams III and Alabama’s Damien Harris – will have better careers than the class of 2016, but the history-making freshmen got the bump.

Nov 24, 2016; College Station, TX, USA; LSU Tigers running back Derrius Guice (5) points to the crowd after scoring a touchdown during the third quarter against the Texas A&M Aggies at Kyle Field. Mandatory Credit: Troy Taormina-USA TODAY Sports

Credit: Troy Taormina-USA TODAY Sports

The ranking for this class is likely to change with Guice’s first year in the spotlight and out of Fournette’s shadow. Williams and Harris face tough competition for carries in 2017 from younger teammates (Whaley and Najee Harris). If Florida’s Jordan Scarlett and Tennessee’s John Kelly rush for 1,000 yards this fall, that would give this class a significant boost in future rankings.