Steven Jackson was a fixture in the Rams' backfield for nine seasons. His departure this offseason has created a job opening for somebody. The problem is, we don’t know who that somebody will be.

Whoever does get the job will be a great pickup in fantasy for 2013. When Jackson was the starter, he posted eight consecutive seasons of 1,000 rushing yards or more. He also never had less than 38 receptions in those eight seasons.

The competition comes down to three guys: Daryl Richardson, Isaiah Pead and Zac Stacy. Among these three, the Rams' backfield only has 108 carries at the pro level. They’re all very young, but they each have different skill sets that make them valuable.

All three guys will make their case to be the starting running back during training camp and the preseason, but right now, it’s not certain who will get the nod.

Richardson was a nice surprise last season. The seventh-round draft pick from Abilene Christian played 314 snaps and produced well when given the chance. The 5'10", 196-pound back carried the ball 98 times for 475 yards (4.8 YPC) and added 24 receptions for 163 yards. He didn’t get in the end zone, but it was still a solid season for a seventh-round rookie playing in a backup role.

That role was expected to be Pead’s job. After all, he was a second-round pick, and the fourth running back selected in the 2012 draft. But Pead only played 42 snaps the whole season. He opened up recently about his rookie struggles, calling his experience “miserable.”

Pead got a late start to offseason practices as a rookie due to a late graduation date, and things didn’t get much better from there. He was late for practices and found himself not seeing the field. He finished his rookie season with just 10 carries for 54 yards.

His sophomore season has already gotten off to a bad start. He was suspended for the first game of the season after violating the NFL’s substance abuse policy. The suspension stems from a July 2012 arrest for marijuana possession. One game isn’t a big deal, though. Jeff Fisher said he feels Pead has a professional approach for the upcoming season.

Fisher also said Pead’s suspension won’t hurt his chances competing for the starting job. After all, there were reports after Pead was drafted that the Rams viewed him as Jackson's successor. The 5'10", 197-pound running back also received comparisons to Titans back Chris Johnson. He’s not as fast as Johnson, but he does have great speed, quickness and vision.

The last piece of this puzzle is Stacy. The Rams selected Stacy in the fifth round of this year’s draft. His 5'9", 216-pound frame makes him a bigger back than both Pead and Richardson. At Vanderbilt, he was a power runner who would run through guys instead of around them.

Stacy has drawn comparisons to guys like Ray Rice and Doug Martin. He doesn’t possess blazing speed (4.55 40), but he’s an effective back who was highly productive in college. Going against tough SEC defenses, Stacy rushed for over 2,300 yards, 24 touchdowns and had a 5.7 yards-per-carry his last two seasons at Vanderbilt.

There are different theories as to who will get the starting job. CBS Sports columnist Clark Judge believes Richardson is the favorite because “he’s the only guy with a resume.” Rams beat writer Jim Thomas expects the Rams to go running back by committee (RBBC).

Fisher was able to make a RBBC work in 2008 with Chris Johnson and LenDale White. They became known as smash and dash, as Johnson finished with 1,228 yards and White with 773. A committee might be how the Rams backfield plays out. All three players can deliver something unique to the team.

Stacy will have the most work to do, since he’s a fifth-round rookie. He could turn into this year’s Alfred Morris and produce right away despite all the odds being against him, but that's a lot to ask.

In mock drafts so far, St. Louis' running backs can be drafted at a cheap price. Richardson is the first one off the board in the seventh round, followed by Pead and Stacy in rounds nine and 10, according to fantasyfootballcalculator.com. If one of these guys does get the starting job, they would be a steal that late. Even if you pick the wrong guy, it’s so late in the draft that it won’t really come back to hurt.