Burton Burns is easily one of the most accomplished assistant coaches in college football.

As the longtime running backs coach at Alabama, he has mentored a pair of Heisman Trophy winners and five first- or second-round NFL draft picks. The overall numbers he has helped compile since joining Nick Saban's staff in Tuscaloosa in 2007 are staggering: The Crimson Tide rank among the top 10 of Power 5 teams in rushing yards, yards per carry and rushing touchdowns during that time.

That's not to mention Burns' former stops at Clemson and Tulane, either, where he cut his teeth and worked with backs such as James Davis and C.J. Spiller.

But Burns, who turns 65 in October, has a new kind of problem on his hands this spring at Alabama. It's a good problem to have, granted, but it's one that will require a deft touch and possibly a scientific calculator to solve.

How do you spread one football among so many talented running backs?

Damien Harris returns as Alabama's leading rusher from 2017, but he'll have to compete for carries with a young and talented backfield. John David Mercer/USA TODAY Sports

Go back to the first day of spring practice to see the issue. Burns, wearing a red Alabama baseball cap, red shorts and a long-sleeve shirt, stood on one end of a beat-up chute on a warm Tuesday afternoon, directing his running backs to get low and sprint under the mesh netting. Damien Harris was first through the drill. Then came Joshua Jacobs. Bringing up the rear was Bo Scarbrough, wearing a black no-contact jersey.

Meanwhile, B.J. Emmons was a couple of yards away working with a member of the medical staff rehabbing his leg at the time. And third in line on the chute was Najee Harris.

That was 2,589 rushing yards and 18 touchdowns on the field at once. It was the team's top four rushers, all underclassmen last season. On top of them, there was Najee Harris, the five-star true freshman who enrolled early with plans on making an impact right away.

It's going to be hard enough for Burns to decide on a starter. Damien Harris, who led the team with 1,065 yards last season, might be the favorite to hold on to the job. But as we saw late in the season before he broke his leg against Clemson, Scarbrough is a 6-foot-2, 228-pound force of nature with the ball in his hands. During the Iron Bowl, SEC Championship and two rounds of the College Football Playoff, he rushed for 454 yards and six touchdowns.

Not to be overshadowed are true sophomores Emmons, who in seven games before an injury rushed for 4.9 yards per carry, and Jacobs, who racked up 585 yards and four touchdowns on 85 attempts.

Only once during Saban's tenure have we seen four running backs garner 40 or more carries in a season, and that was in 2009 when Mark Ingram had a supporting cast of Trent Richardson, Roy Upchurch and Terry Grant. Even then, you had Greg McElroy rushing the ball only 54 times at quarterback, compared with the 191 rushes Jalen Hurts had as a true freshman quarterback last season.

Unless Alabama runs a Wing-T, it's going to be hard to get carries for the four returning running backs, along with Hurts and Najee Harris.

And make no mistake, the newcomer isn't a good bet to redshirt.

“Najee is a very good all-around player, one of the best players in the country, according to a lot of people's evaluation,” said Saban, who isn't exactly one to lead the hype machine. “He's got great size, he's got great speed, he's very fluid and smooth athletically, very complete. Has very good hands, good route runner, has special production as a player.”

Good luck keeping that level talent off the field, especially when he arrived in time for spring practice ready to play at a rock solid 6-foot-2 and 227 pounds.

Maybe we'll see Damien Harris and Scarbrough take fewer carries to get the others involved. Or maybe new offensive coordinator Brian Daboll will put multiple backs on the field at once.

You'll remember that as a senior in 2015, Kenyan Drake had a career-high 29 receptions when Derrick Henry rumbled his way to the Heisman Trophy. Jalston Fowler's stocky frame helped him split time as a running back and H-back the year before that.

Who knows? Scarbrough, who played receiver in high school, and Najee Harris, who seems to possess good hands, could be options to split out as slot receivers. Maybe Emmons and Jacobs, who are more compact runners, could double as lead blockers, too.

It's going to take some creativity from Burns and Daboll.

There might be a few long nights finding the right formula to make all the pieces work and keep everyone happy, but at the end of the day it will be a pleasant problem to solve.