Oakland Raiders defensive end Richard Seymour has been fined $25,000 but has escaped a suspension for his attack on Pittsburgh Steelers quarterback Ben Roethlisberger.

The Steelers triggerman received an open-handed smack in the mouth from Seymour as the Raiders were beaten 35-3 in Pittsburgh.

The NFL has been clamping down hard on helmet-to-helmet hits, and late hits on quarterbacks, but slaps in the face have not been an issue they thought they would have to deal with.

Seymour has been handed a fine, but the Steelers are incensed that he has not been banned and can line up for the Raiders again on Sunday against Miami.

"It blew my mind," Roethlisberger said of the hit from the five-time Pro Bowl defensive lineman.

Seymour smacked Roethlisberger after the QB had thrown a touchdown during the win, when the Steelers man had run over to his team-mates to stop some pushing and get them prepared for the extra point.

Steelers coach Mike Tomlin refused to criticise the league for the lack of a Seymour suspension, saying he will be trying to calm his players down in time for their next game on Sunday.

Tomlin had another reason to criticise league officials after the Steelers were hit with a record 163 yards of penalties against the Raiders - a team record.