ALAMEDA — The Raiders may be without leading receiver Michael Crabtree against Denver after he missed practice Friday because of the lingering effects of a chest injury he suffered during the team’s loss to Washington.

Crabtree had been limited earlier in the week but was held out of the Raiders’ final workout before the team flies to Colorado and is listed as questionable. Coach Jack Del Rio declined to say whether Crabtree had suffered a setback and said a decision may not be made until Sunday.

“(We) have a couple of guys on the injury report that are questionable,” Del Rio said. “We’ll see how it goes. Whether they’ll be able to go or not, we’ll make that determination as we get closer to the game.”

Crabtree has 13 catches for 170 yards and a team-high three touchdowns through three games but is coming off his worst performance of the season when he and Amari Cooper were each held to one catch in the Raiders’ 27-10 loss to the Redskins last week.

Crabtree, who has played in all 35 regular-season games since signing with Oakland in 2015, was knocked out of the game following a hard hit early in the fourth quarter.

Crabtree, 30,was also the primary target of a postgame tirade by Redskins cornerback Josh Norman, who accused Crabtree and Cooper of talking trash before the game.

Denver cornerback Aqib Talib, who snapped a chain from around Crabtree’s neck in the final regular-season game of 2016, also had some choice words for Crabtree this week but Crabtree has stayed quiet. He declined interview requests Wednesday and did not appear in the team’s locker room Thursday or Friday during the media’s 45-minute access period.

If Crabtree is unable to play — he last missed a game in 2013 — the Raiders will likely lean more on Seth Roberts and Cordarrelle Patterson to pick up the slack.

Elsewhere on the team’s injury report, cornerback Gareon Conley (shin) was limited for a second consecutive day and is questionable.

Safety Keith McGill (foot) is also questionable.

Cooper was limited earlier in the week with a knee injury but was a full participant each of the past two practices.

SMITH ENTERS PLEA

Los Angeles prosecutors say Oakland Raiders cornerback Sean Smith has pleaded not guilty to beating his sister’s boyfriend in July.

The Los Angeles County District Attorney’s Office said Smith appeared in court Friday to face assault and battery charges.

Smith is accused of beating the victim and stomping on the man’s head in Pasadena on July 4.

Prosecutors said a judge ordered Smith to stay away from the victim. He’s due back in court Nov. 6.

Smith’s attorney has said he maintains his innocence and will fight the charges.

Smith previously played for the Miami Dolphins and the Kansas City Chiefs. Smith pleaded guilty in 2015 to a driving under the influence charge in Kansas City and was sentenced to two years of probation.