Quarterback Andy Dalton suffered a neck injury Saturday night, apparently when he converted a fourth-and-one from the half-yard line to give the Bengals a 7-0 lead over the Bears with 4:17 left in the first quarter at Paul Brown Stadium on the way to Cincinnati's 21-10 victory.

But head coach Marvin Lewis said Dalton is fine and took him out of the game for "precautionary," reasons on a night that looked to end with no major injuries. With none of the starters expected to play Thursday night in the pre-season finale, they all look healthy for the start of the season.

Dalton had been expected to play the first half with the first offense, but AJ McCarron took over on the second drive with 14:47 left in the half and went on to deliver a 31-yard touchdown pass to wide receiver Marvin Jones with 6:24 left in the half to make it 14-0 as Bengals quarterbacks hit all 12 passes in the first half. McCarron went 6-for-6 (87 yards) when he floated a 25-yarder to tight end Tyler Eifert  to set up running back Jeremy Hill's one-yard touchdown run with 1:56 left in the half to make it 21-0.

The next time we see Dalton is most likely Sept. 13 in Oakland in the opener. It appeared not to be serious since he stayed on the sidelines

 "We wanted to come out and set the tone right away after last week," Dalton said. "We wanted to come out and play fast, and that's exactly what we did. We mixed in runs and passes and controlled the ball. It got a little tough at the end, but that just made us want to score more. I knew I'd get in. I knew our line would do it for me."

.As good as the offense was, the first-team defense suffocated Bears quarterback Jay Cutler and friends. The Bears had to punt on their first four series, featuring a sack by left end Carlos Dunlap, a pressure by right end Wallace Gilberry, and a pancake tackle on a run by defensive tackle Geno Atkins.

Linebacker Chris Carter racked up a sack on the Bears' last series of the half, but that didn't prevent Robbie Gould's 34-yard field goal in the last minute.

Dalton completed all six of his passes for 52 yards and also had an eight-yard scramble for a third down. He ducked between center Russell Bodine and right guard Kevin Zeitler for the touchdown when he apparently suffered the injury on the 16th snap of the drive.

That was one more snap than the Bengals took on the first six series in Tampa Monday night and just seven more snaps than Dalton took against the Bucs.

And Dalton led the big rebound, five days after they went 1-for-6 on third down in Tampa. On Saturday Dalton converted a pair of third downs, one on an eight-yard scramble and one on a quick five-yard shot to running back Giovani Bernard lined up in the slot before converting the fourth for the touchdown.

Dalton hit five different receivers and the two big ones came back-to-back to wide receiver Rex Burkhead lined up in the slot. Burkhead fried linebacker Shea McClellin for a 10-yard gain over the middle and then made a leaping 24-yard catch over the middle to put the Bengals at the Bears 14.

In what has been characterized as a dress rehearsal in the third pre-season game, Bengals offensive coordinator Hue Jackson opened his Pandora's Box on the 16 plays for the first time this season. He immediately turned to rookie left tackle Jake Fisher in his NFL debut and used him in the heavy package as a third tackle. He also split his tackles to the hash marks on one snap, and he also put two running backs, Burkhead and Jeremy Hill, in the slot on another snap.

McCarron didn't blink an eye in matching Dalton's 6-for-6 despite taking some surprising pressure behind the first offensive line.  Marvin Jones went over Bears cornerback Tracy Porter for a spectacular 43-yard catch, but it was wiped out on a holding call against left tackle Andrew Whitworth.

But McCarron re-grouped to convert three third downs. He started it all with a 15-yard back-shoulder throw to wide receiver A.J. Green working on cornerback Tim Jennings as he took a shot from linebacker Pernell McPhee bearing down on the right side as he let it go. On third-and-nine McCarron found Marvin Jones running across the middle at the Bears 10 and Jones kept running and cut it back for the 31-yard touchdown.

After safety Reggie Nelson sniffed out a third-and-10 check-down pass to force the fourth straight punt, McCarron overcame more adversity. Hill's 12-yard run on a power play with the help of Fisher was negated by a holding call on right guard Kevin Zeitler. But Hill responded with his first 20-yard run of the preseason with a 26-yard burst-and-bolt behind fullback Ryan Hewitt's crushing lead block on McClellin.

McCarron then floated the 25-yarder to Eifert down the left sideline as he burned inside linebacker Christian Jones to put the ball on the 3.  From the 1, left guard Clint Boling pulled to the right, but Hill broke it outside and shook off safety Brock Vereen's ankle tackle for the TD to make it 21-0.

The offensive line had a tough time getting dug in. Not only did they have the two penalties, but they got stopped on one third-and-one and got stopped from the 3, 2, and 1 before Dalton scored.

Cutler hit 12 of 15 passes, but for only 90 yards in the half. The Bengals did a good job on running back Matt Forte, holding him to 16 yards on six carries.

"We came out with more focus and more energy. We knew we had to do that after last week," said safety George Iloka. "We've got a lot of veteran leaders, and even thought it's just preseason, you never want to put two bad performances back to back."

Iloka had an active four tackles in the half and linebacker Vincent Rey led the way with six tackles.

All-Pro returner Adam Jones lined up for his first punt of the season and he tried right, tried left and came back to the middle and lost five yards, but it was worth the price of admission.

The second half began with the Bears' first-teamers staying in against the Bengals' backups and it was tough on Cincinnati's backup line consisting of Fisher at left tackle, Dan France at left guard, T.J. Johnson at center, Eric Winston at right guard, and Matt O'Donnell at right tackle. McCarron kept getting pummeled in the pocket and one drive ended when O'Donnell couldn't fend off outside linebacker Lamar Houston for a sack.

As the game veered into the fourth quarter, Johnson was called for a hold when he got knocked back on a run and on the next snap, a sweep to running back Cedric Peerman, Fisher was called or another hold. But it was wiped out when Peerman had the ball poked out of his arms from behind for the first turnover of the night with about 12 minutes left in the game.

But the Bengals backup defense held on pretty well. Early in the third quarter, the Bears converted a third-and-one, but right guard Kyle Long was called for a hold. On third-and-11, rookie defensive lineman Marcus Hardison tipped Cutler's final pass of the night to force the fifth punt of Cutler's six series.

Carter had another sack, but it was wiped out when rookie cornerback Josh Shaw was called for illegal contact in the secondary.

At the end of the third quarter, the Bengals had effectively blunted a Chicago running game that came into the game averaging 166 yards on 67 yards.

They could only score on a blocked punt with about five minutes left in the game, which doesn't happen around these parts very much. In fact, it's never happened to Bengals punter Kevin Huber in the regular season. The last time the Bengals had a punt blocked for a touchdown in real games was in 2008, the year before Huber arrived.

On this play, Bears wide receiver Ify Umoodu ran past some Bengals on the edge (he went inside safety Shiloh Keo) and basically took the ball off Huber's foot for an eight-yard return for a touchdown.

McCarron ended up getting sacked again and gave way to Keith Wenning midway through the fourth quarter. He showed quite well, finishing with a 117 passer rating on 12 of 17 passing for 149 yards. McCarron made a heck of a play on his final throw. He avoided a sack, wriggled out of the pocket and as he ran to the sidelines he threw a strike to rookie tight end C.J. Uzomah on the sidelines, but Uzomah  dropped it. PREGAME NOTES:After two weeks of waiting it appeared Saturday night that the Bengals offensive line arrived finally fully healthy for the third pre-season game at Paul Brown Stadium against the Bears.

That meant right tackle Andre Smith (unknown ailment) would probably start for the first time this year and first-round pick Jake Fisher (shoulder) would most likely back up left tackle and maybe play some guard in his NFL debut. Also, backup guard center Trey Hopkins (leg), who practiced for the first time in nearly three weeks on Wednesday, didn't appear on head coach Marvin Lewis' Not Expected To Play List that he released in pregame, indicating Hopkins would play his first game of the year.

Last season Hopkins was headed to a roster spot as an undrafted free agent out of Texas until he broke his leg in the preseason and he apparently is still trying to recover. Now he's in a battle to be one of the projected nine offensive linemen to make the final 53-man roster. With Fisher, Eric Winston and T.J. Johnson apparently leading the backup derby behind the five starters, spots are at a premium.

The Bengals defense looked like it took a hit for the Bears. Nickel backer Emmanuel Lamur (hamstring) and backup cornerback Darqueze Dennard (hamstring) weren't expected to play.

Backup tackles Pat Sims (thigh) and Brandon Thompson (unknown) weren't on the Not Expected To Play List, but  don't expect them to play Saturday night or in Thursday night's pre-season finale in Indianapolis. And that probably goes for Dennard, too.

Also not expected to play Saturday was backup cornerback Brandon Ghee (hamstring), whose return to the club this offseason has been plagued by the injuries that stalked him in his first stint in Cincinnati and he has yet to play in a game. Wide receiver Tevin Reese (hamstring) also wasn't expected to play.

Also not expected to play were guys that have yet to play in a game, wide receiver Onterio McCalebb (hamstring) and right end Michael Johnson (knee), or guys that have yet to get off the rehab field in linebackers Vontaze Burfict and Sean Porter and rookie left tackle Cedric Ogbuehi.

For game captains, head coach Marvin Lewis chose wide receiver A.J. Green, quarterback Andy Dalton, cornerback Adam Jones, left end Carlos Dunlap, and wide receiver Brandon Tate.

Rookie Tom Obarski kicked the game off with a touchback, but veteran Mike Nugent was expected to get his first work of the season with field-goal duty.