CINCINNATI — Kyle Boller gave the St. Louis Rams one frightening moment along with a little bit of relief.
Boller played better Thursday night in his second game filling in for Marc Bulger, completing a flurry of short passes during a 24-21 victory over the Cincinnati Bengals.
The one problem: He didn't duck.
Boller got his helmet knocked off on a hit by linebacker Keith Rivers at the end of an 8-yard scramble, waiting too long to start his slide. Unfazed, Boller got to his feet, found his helmet and completed his next two passes, including a 3-yard shovel pass to running back Samkon Gado for a touchdown.
His too-late slide couldn't help but terrify the Rams, who lost Bulger to a broken pinkie finger on his passing hand before the last game and couldn't afford another quarterback setback. Bulger is hoping to be ready for the season opener Sept. 13 at Seattle.
Boller struggled as his replacement last week in a 20-13 loss to the Falcons, but seemed much more comfortable against the Bengals. He completed 14 of 20 for 96 yards, heading for the bench after the opening series of the third quarter.
Both teams were missing their starting quarterbacks, turning the game into a preview of how it might be if their injuries linger. The Bengals were reminded that they really need Carson Palmer back for their opener against Denver.
J.T. O'Sullivan was sacked three times, lost a fumble and had two passes batted away at the line. His best moment was an improvised underhand pass to running back Brian Leonard that went for 25 yards and set up a touchdown. O'Sullivan was 7 of 13 for 94 yards while playing into the third quarter.
With Palmer sidelined the last two games by a sprained left ankle, the offense has moved the ball in spurts but failed to get many points because of penalties and mistakes. O'Sullivan's fumble at the Cincinnati 20-yard line set up the Rams' second touchdown.
Running back Bernard Scott, a sixth-round draft pick from Abilene Christian, had a fumble that safety James Butler returned 73 yards for a touchdown. Butler also intercepted one of Jordan Palmer's passes in the third quarter and returned it 68 yards before the third-string quarterback tackled him.
The Bengals have lost five fumbles and thrown three interceptions in three preseason games.
"Obviously, you can't have turnovers like we had," Bengals coach Marvin Lewis said. "That was still our Achilles' heel in the first half, as it has been for too much of this preseason. We can't allow that to continue."
Quan Cosby, an undrafted receiver from Texas, returned the Rams' first punt 49 yards for a touchdown, breaking through the front line of defenders into the clear. He ran past punter Donnie Jones to get to the end zone.
Jones also had a punt returned 44 yards by Tom Nelson in the third quarter.
NOTES: Rams K Josh Brown was wide left on a 50-yard field goal try at the end of the first half and wide again on a 51-yard attempt with 3:10 left in the game. ... Bengals S Chinedum Ndukwe suffered a shoulder injury in the third quarter. ... Chris Henry caught a 54-yard touchdown pass from Jordan Palmer in the fourth quarter, beating rookie CB Bradley Fletcher down the left sideline. Henry has all three of the Bengals' touchdown catches in the preseason.