Receiver Amari Cooper was on the field for 69 of the 74 snaps the Raiders’ offense ran in Monday night’s 33-13 loss to the Rams. Quarterback Derek Carr threw to him three times.

It was hardly the involvement expected when head coach Jon Gruden said in the offseason that Cooper would be the “focal point” of the Raiders’ passing game. Cooper finished with one catch for 9 yards.

Carr later said the Rams schemed to take away both Cooper and Jordy Nelson with cornerbacks Marcus Peters and Aqib Talib as well as safety help. Gruden said the Raiders “did call (Cooper’s) number several times.” But, he added, “We’ve got to do a better job as a coaching staff getting him the football.”

One strategy, it appears, is to get Cooper more help.

According to an NFL Network report, the Raiders were nearing an agreement Tuesday afternoon to re-sign receiver Martavis Bryant, whom they waived amid the 53-man roster cut downs Sept. 1. A source confirmed Bryant was returning on a one-year deal.

The move would continue a strange saga between the Raiders and the productive but troubled receiver. In April, Oakland traded a third-round pick to the Steelers for Bryant, who presented a downfield threat with his mix of size (6-foot-4) and speed. Bryant’s play in training camp drew criticism from Gruden, who also dubbed him the “white tiger” for missing multiple practices.

Bryant was suspended twice by the NFL while in Pittsburgh for violating the league policy on substance abuse, and ESPN reported Sept. 1 that Bryant was facing a third suspension under the policy. However, a suspension has not been announced and Bryant remains eligible to play.

Gruden told reporters Sept. 2 that the Raiders waived Bryant because “other players outperformed him” and actually mentioned the possibility of a reunion “next year.”

The Raiders had trouble getting their receivers involved Monday against the Rams, as Nelson, Cooper and Seth Roberts combined for five catches for 43 yards, and their lack of a deep threat to open opportunities for those players underneath was evident.

Part of the Raiders’ plan Monday was to involve tight end Jared Cook and running back Jalen Richard in the passing game. Cook benefited with nine catches for 180 yards, setting the franchise record for receiving yards in a game by a tight end. Richard was targeted 11 times by Carr, finishing with nine catches for 55 yards.

The use of Richard as a receiver, Gruden said, was one reason Marshawn Lynch played just 27 snaps Monday night, totaling 11 carries for 41 yards. Gruden also said Lynch had “a little bout of sickness” during the game, “so we put him in the garage for a minute.”

Although the Raiders had five active receivers Monday, they used only three on offense, playing Dwayne Harris and Keon Hatcher solely on special teams. Brandon LaFell was inactive after signing with the Raiders on Sept. 3. Gruden said LaFell was “not quite ready” to play but said, “He has upside. Hopefully, we can get him up here soon.”

Before news emerged of a possible reunion with Bryant, Gruden cited Cooper when asked if the Raiders still have a deep threat at receiver. The numbers, though, don’t bear out that assessment. After surpassing 1,000 receiving yards in each of his first two NFL seasons, Cooper has been held under 10 yards six times in 15 games since the start of last season.

It’s a trend that Gruden and the Raiders would like to see end, beginning Sunday in Denver.

“We’ll have to get Amari going this week,” Gruden said. “It’s easier said than done when you’ve got (Denver cornerback Bradley) Roby and Chris Harris, and a fierce pass rush that doesn’t let you drop back and let these routes develop.

“You’ve got guys that can really hum around the edge, and you’ve got to be creative in how you get guys the ball deep. And we’re going to have to try to get Amari going.”

Briefly: Gruden said the Raiders will sign a long snapper and worked out “several candidates” Tuesday to replace Andrew DePaola, who suffered a knee injury on his first snap Monday night.

Gruden did not give specific injury updates, but said defensive tackles Justin Ellis and P.J. Hall injured ankles Monday. He also said Carr, who took a low hit from Aaron Donald early in the game, was “sore.”

Matt Kawahara is a San Francisco Chronicle staff writer. Email: mkawahara@sfchronicle.com Twitter: @matthewkawahara