Raiders' Marshawn Lynch out for extended period with groin injury

Stephen A. blames Gruden for Raiders' slow start (1:24)

Stephen A. Smith thinks the blame for the Raiders' poor start rests on coach Jon Gruden, not quarterback Derek Carr. (1:24)

Oakland Raiders running back Marshawn Lynch will miss an extended period of time with a groin injury, a source confirmed to ESPN.

The Raiders have discussed placing Lynch on injured reserve but no decision has been reached, the source said.

The news was first reported by NFL Network, which said Lynch would be sidelined for at least a month.

Lynch has rushed for a team-high 376 yards on 90 carries (4.2 yards per carry) and three touchdowns this season. He also has 15 receptions for 84 yards.

ESPN's Dan Graziano contributed to this report.