Marable was stopped in a 65-mph zone around 1 a.m. Sunday morning on Interstate 5, according to the Gazette-Times in Corvallis, Ore.
Marable also was warned for failure to have proof of insurance and registration for the car, a 2005 Nissan Altima, which was not his own.
It was not immediately clear whose car it is or whether there were any passengers, the newspaper said. The fine for driving a vehicle faster than 100 mph in Oregon is $1,150.
In the past week, Riley also suspended two other cornerbacks indefinitely: Sean Martin for allegedly driving under the influence, according to police reports, and Mishawn Cummings for an undisclosed violation of team rules.
Marable played in all 12 of the Beavers' games last season, primarily on special teams, with two tackles on defense and 322 yards on 13 kick returns.
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