Doctors initially thought the injury wasn't serious. He was sent for tests. The injury happened during the team's second practice of training camp.
''From everything right now, it seems like everything should be OK,'' coach Marvin Lewis said.
Johnson returned to the Bengals after spending one season with the Buccaneers. The Bengals are hoping he revives a line that didn't get much pressure on the quarterback last season. Cincinnati finished last in the league in sacks.
The Bengals also are counting on tackle Geno Atkins to play better now that he's had a full year to recover from knee surgery.
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