High-volume NFL running backs are harder and harder to find. In 2002, the first year the league expanded to 32 teams, the No. 1 running back on a team’s depth chart got more than a third of his team’s opportunities, on average. In 2018, that dropped to 23 percent, one of the lowest average marks over the past 17 years.

Not all of the high-volume backs of last year are a sure thing to repeat in 2019, either. Of the 14 running backs who met or exceeded the 23 percent threshold in 2018, Dallas Cowboys running back Ezekiel Elliott led the position in opportunity share (42 percent). But the 24-year-old, who has two years remaining on his rookie contract, has been holding out in search of a new deal, opening the door for rookie Tony Pollard to impress in camp. Los Angeles Chargers running back Melvin Gordon (27 percent) also is holding out for more money and may not play in 2019.

Todd Gurley accounted for 34 percent of the Los Angeles Rams’ offensive opportunities last season, but NFL Network Insider Ian Rapoport reported in June “that it is understood in Los Angeles that Gurley will no longer be the bell-cow back that he was over the first four seasons of his career” after suffering a knee injury.

Washington Redskins running back Adrian Peterson will have to share time with second-year pro Derrius Guice, who missed his entire rookie season due to an anterior cruciate ligament tear. A healthy Chris Thompson, Washington’s pass-catching back, could also steal some looks in 2019.

Chicago’s Jordan Howard (27 percent share) was traded to the Philadelphia Eagles for a conditional fifth- or sixth-round pick in 2020, and Tampa Bay’s Peyton Barber (26 percent) will have to hope second-year running back Ronald Jones, who impressed new head coach Bruce Arians in camp, won’t siphon too many opportunities. Finally, Houston’s Lamar Miller is expected to miss the season with a knee injury.

That leaves just seven running backs with a realistic chance of maintaining their position with their team, five of whom are likely first-round fantasy picks: Saquon Barkley, David Johnson, Christian McCaffrey, Alvin Kamara and James Conner. The other two, Joe Mixon and Chris Carson, should be available later in the draft.

Joe Mixon, Cincinnati Bengals (2.07 ADP)

Mixon, a third-year pro out of Oklahoma, had a breakout season in 2018, touching the ball 280 times with zero fumbles for 1,464 yards from scrimmage and nine total touchdowns (eight rushing, one receiving). New head coach Zac Taylor, an assistant coach under Sean McVay with the Los Angeles Rams, plans to run a similar scheme in Cincinnati to that of his former team, giving Mixon “more advantageous matchups and running lanes.”

That could translate to a huge uptick in fantasy scoring for Mixon. He averaged nearly five yards per carry last season (11th best, league average is 4.4) and saw 11 of his carries go for 20 yards or more. Only Barkley had more explosive runs in 2018.

Chris Carson, Seattle Seahawks (3.12 ADP)

The Seahawks were the most run-heavy team last season in score-neutral situations (53 percent of plays with the score within a touchdown), allowing Carson to finish with 247 carries in 14 games, good enough for seventh-most last season. And offensive coordinator Brian Schottenheimer said he would like Carson to be more involved in the passing game after seeing just 24 targets in 2018.

“We need to get that number around the fifties,” Schottenheimer told NBC Sports. “That would be a great situation for us.”

The Seahawks targeted their running backs just 85 times last season, the third-fewest in the NFL.

Note: A prior version of this article listed Lamar Miller among players to target; he suffered a torn anterior cruciate ligament in late August and is expected to miss the season.

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