OAKLAND, CALIF. ? Oakland linebacker Bill Romanowski was placed on injured reserve Thursday night.

The 37-year-old Romanowski has missed the last four games after a series of concussions earlier in the season sidelined the 16-year veteran. He will remain with the Raiders for the rest of the season as a defensive adviser, coach Bill Callahan said.

“I don’t think there’s been a more dominant player than Bill at that position,” Callahan said.

Romanowski, in his second season with the Raiders, has also played for Philadelphia, San Francisco and Denver.