Ameer Abdullah had become the forgotten man in the Detroit Lions' running back room, and on Tuesday that finally made him expendable.

The Lions waived Abdullah after 3 1/2 seasons to make room for free-agent wide receiver Bruce Ellington.

The team also brought back running back Zach Zenner, who was waived with an injury settlement in September.

A second-round pick out of Nebraska in 2015, Abdullah showed plenty of promise as a rookie, when he started nine games and ran for a team-high 597 yards.

But as has been common with Lions running backs over the years, Abdullah's production and play time quickly tailed off.

He suffered a Lisfranc injury early in his second season that limited him to just two games, was benched for ineffective play late last season, and toiled at the bottom of the depth chart this year after the Lions signed LeGarrette Blount in free agency and traded up to take Kerryon Johnson in the draft.

Johnson leads the Lions with 89 carries for 503 yards and has gotten the bulk of the work at running back the last three weeks. He has two 100-yard rushing games on the season.

Abdullah has appeared in just three games this year, where he served primarily as the Lions' kick returner. He has one carry for 1 yard in 11 offensive snaps, and fumbled away a key kick return in the first half of a Week 8 loss to the Seattle Seahawks.

Lions coach Matt Patricia offered a vote of confidence in Abdullah after his fumble, the eighth of his career, saying, “as far as I’m concerned with Ameer ... I have a lot of confidence (in him)."

Zenner, a fan favorite who played sparingly in three seasons with the Lions from 2015-17, provides more special-teams value than Abdullah and gives the Lions insurance at the running back position behind Johnson, Blount and Theo Riddick.

Riddick saw extra playing time at the slot receiver position as a replacement for Golden Tate in last week's loss to the Minnesota Vikings, but could lose some of those snaps to Ellington.

A fourth-round pick by the San Francisco 49ers in 2014, Ellington has 56 catches for 637 yards in parts of five seasons with the 49ers and Houston Texans.

He played in three games for the Texans earlier this year, and was waived from injured reserve last week.

Ellington, who suffered a hamstring injury in Week 3, was one of several wide receivers who recently worked out for the Lions along with Brandon Marshall and Jeremy Kerley.

Contact Dave Birkett: dbirkett@freepress.com. Follow him on Twitter @davebirkett. Download our Lions Xtra app for free on Apple and Android!