Few people dive into a new profession at the top of their game. Most take a bit to adapt, regardless of how much schooling or training or practice they have received beforehand.

This notion doesn’t apply as well to NFL running backs. It is a position that yields a remarkably short-shelf career for most players. Those who do stick around routinely don’t last as long as players at other positions — there are few Frank Gores and Adrian Petersons. Those who do defy Father Time with careers that span more than a decade often see a dramatic dip in production in those waning years — see: Frank Gore and Adrian Peterson.

That puts an added emphasis on youth at the running back position. And this focus obviously carries over to the fantasy realm. Young running backs are highly coveted in fantasy drafts. They come at a cost that makes it difficult not to have them in your starting lineup.

Yet, fantasy dependence is no guarantee of fantasy success, as this year’s rookie class is showing. Josh Jacobs widely was touted as the most talented rookie. But a lack of confidence in the Raiders offense lent weight to the notion that David Montgomery was in a better situation in Chicago.

Some flocked to the talented Miles Sanders, assuming Eagles coach Doug Pederson would abandon his history of using backfield committees . There were those who used a deeper pick on Buffalo’s Devin Singletary, assuming he eventually would usurp Gore as the feature back.

None has lived up to optimistic projections, but Jacobs has come the closest. He had a huge day Sunday, 26 carries for 123 yards with two touchdowns. But that also was his first big fantasy day since Week 1, when he scored twice despite poor efficiency (just 85 yards on 23 carries).

But that is two more big days than Montgomery has had. He has yet to top 14 fantasy points in any game. Even removing Week 1, when he split carries with Mike Davis, in the four games since, Montgomery is averaging just 11.3 fantasy points.

Jacobs is averaging a robust 4.9 yards per carry but Montgomery just 3.3. The difference in efficiency is stark. And the Raiders have beaten the Colts and Bears in consecutive weeks, so the notion the Raiders would often be playing from behind, undermining Jacobs’ opportunities, is not as big of a worry as it once was.

Jacobs is an every-week starter. Montgomery is a nervous Flex option. If you can get a wide-eyed leaguemate still focused on Montgomery’s potential to pay above the current market value, jump on such a deal.

The news is even worse for Sanders and Singletary. Sanders is mired in a committee with Jordan Howard, with Howard the goal-line guy. Singletary will have a hard time wrestling a full workload from the veteran Gore, especially if Singletary can’t stay healthy.

Their value is too low to warrant trade interests, and their ceilings still better than what you’re going to find on waivers. Park them at the end of the bench and hope things turn around.