Rivers was hurt when Steelers receiver Hines Ward leveled him with a straight-up block during Pittsburgh's 38-10 victory on Sunday. The first-round draft pick walked off the field without assistance and went for tests that detected the fracture.

After watching a video of the play on Monday, Bengals coach Marvin Lewis didn't take issue with the rattling block.

"There was not a foul," Lewis said. "There were no flags thrown."

The hit came on the fourth play of the game. Ben Roethlisberger completed a 6-yard pass to Matt Spaeth near the right sideline, and Rivers tried to chase him down. Ward was farther downfield, saw the linebacker coming and leveled him.

Rivers is 2 inches taller and weights 35 pounds more than Ward, who is known as one of the league's toughest blockers. Ward already has been fined by the league twice this season for hits that weren't penalized during the game. Ward initially reveled in the hit, then showed concern for Rivers when the rookie didn't get up right away.

"I'm not doing anything illegal," Ward said after the game Sunday. "It was a clean hit. I didn't stand over the guy or anything. I just celebrated the same as a guy does when he gets a sack.

"We'll see. I'm not going to change my ways. If they're going to keep fining me for that, then I'm going to get fined all year. I don't know if I hurt him or not, but that wasn't my intention."

Bengals receiver T.J. Houshmandzadeh saw nothing wrong with the block.

"The guy doesn't see you coming, who doesn't do that?" Houshmandzadeh said on Monday. "Keith didn't see him coming, he cracked back on him and it just was unfortunate what happened. But every receiver in the league would do that, if they had an opportunity. They just don't get them too often."

Lewis also ruled out quarterback Carson Palmer for the game Sunday in Houston. Palmer will rest his sore passing elbow for a second straight week. It's unclear whether he will play again this season. For now, Palmer is trying to see if the elbow heals with rest. If not, he has an option of having surgery.

Tests found that rookie receiver Andre Caldwell suffered a stress fracture in his left foot during the loss to the Steelers. He's expected to be sidelined for at least the next two games heading into the Bengals' bye week.

Caldwell, a third-round pick from Florida, hurt the foot on one of his three kickoff returns.

"It wasn't that bad," he said Monday, wearing a protective boot on the foot. "I felt it pop, so I knew something was wrong. Last night it got a little more intense after the Adrenalin wore off."