The whole world changed again with 11:38 left in a first half the Broncos took a 7-3 half-time lead at Paul Brown Stadium when A.J. Green grabbed his toe two steps into his route and fell down in a heap as quarterback Jeff Driskel suffered a sack. Green, returning for the first time since he hurt the toe on the last offensive snap before the bye on Oct. 28, could barely limp back to the bench. When he got there the usually impassive Green slammed his helmet to the ground and once he was on a cart to take him to the locker room he put his head in his a hands. The question wasn't if he was done for the day. That was clear. The question is if he's done for the year.

And the sack given up by the middle of the offensive line made it third-and-25 and symbolized the challenges faced by Driskel in his first NFL start, which began on the first three drives at the 5, 12, and 16. He was driving to a tying touchdown in the last minute of the half with the obligatory leaping 22-yard catch by wide receiver Tyler Boyd over the middle on third-and-11 and a 14-yard run off a bolt by running back Joe Mixon that gave them a first down at the Denver 7 with 25 seconds left and Mixon 59 yards on nine carries.

But when right tackle Bobby Hart gave up pressure to Von Miller off the edge and Miller grabbing every body part he could, Driskel flung it miles out of bounds. Even though tight end C.J. Uzomah was in the vicinity they hit Driskel with a crushing intentional grounding penalty. Why not? It was the Bengals' eighth penalty of the half for 65 yards, giving them 21 flags in the last six quarters. With no Green in the vicinity, Driskel over threw wide receivers John Ross and Cody Core on the next two snaps and Randy Bullock saved the drive on a 35-yard field goal with 12 seconds left that wasn't as easy it sounds with a tricky 17 mile-per-hour wind haunting the kickers on a sun-splashed 60-degree day.

The athletic Driskel, 13 of 20 in the half for 94 yards with surprisingly just one rush (for a loss), finally got the ball at his 40 after starting at his 5, 12 and 19. It happened when Brandon McManus couldn't negotiate the wind on a 50-yard field goal try.

But they ended up looking at a third-and-35 from their 15 after holding calls on right guard Alex Redmond and center Billy Price and a false start on Trey Hopkins making his first start at left guard. Throw in outside linebacker Von Miller bulling Redmond into Driskel to share a sack with tackle Shelby Harris and it marred a badly needed solid effort by the defense.

Rookie defensive end Sam Hubbard picked up his fourth sack of the year to force the missed field goal and on the series before that safety Shawn Williams blew up rookie running back Phillip Lindsay on third-and-one to force a punt when he ran past DaeSean Hamilton.

But they couldn't survive the flag fest. And they couldn't survive a killing third-and-10 conversion even though Broncos quarterback Case Keenum had to scrape a shot-gun snap off the turf and run to the sidelines. Linebacker Nick Vigil, just coming back from missing nearly two months with a knee injury, got beat in coverage by Devontae Booker even though he was called for holding. That set up Lindsay's no-touch six-yard touchdown run (the closest player was right tackle Billy Turner when he fell down) to make it 7-0 with 1:56 left in the half.

The Bengals kept the still-dangerous Lindsay relatively in check with 57 yards on 11 carries in the half, but Driskel end up out-passing the struggling Keenum with the Bengals keeping him to seven of 15 for 77 yards.

Driskel's first drive started at his own five and got helped by 40 yards on Mixon's first four carries. Mixon broke one for 23 yards off Driskel's zone read riding off the double team block of Price and Redmond. Before that he bulled for a first down on third-and-one. Driskel hit four of his first five passes for 17 yards and they were of the safe variety, a quick wide receiver screen to Boyd and a seven-yard crosser to Green on third-and-16.

It was third-and-16 because Clint Boling, making his third NFL start at left tackle in his 107th NFL game, was called for a block in the back when he tried to get down field.

The Bengals' special teams continued to be haunted by flags. On the next snap, rookie tight end Jordan Franks false started on Kevin Huber's punt. After the Bengals forced a three-and-out (the linebackers clogged the passing lanes on third down and Keenum offered a weak incompletion), cornerback KeiVarae Russell was called for an illegal block on Alex Erickson's punt return. So Driskel's second drive started at his own 12 and it wasn't as productive as the first despite an 121yard throw to Ross on a nice slant. The drive blew up when Driskel kept on a zone read, avoided an unblocked Miller on the edge but lost three yards when the Broncos rallied and Driskel went down quickly as instructed, On third-and-eight he tried to hit running back Giovani Bernard over the middle but it was incomplete as the Bengals sought an interference on Todd Davis' plastered coverage.

For the first time since the bye and two home games, the Bengals defense forced a punt in the first half after nine straight touchdown drives. Denver still nicked them in the first drive of the game for 31 rush yards, 27 on three Lindsay runs in which the defense failed to set the edge, but on third-and-six cornerback Dre Kirkpatrick supplied coverage on the side-line sticks.

Moments before Green went down the Broncos saw Pro Bowl cornerback Chris Harris carted off the field with a calf injury.

And Kirkpatrick, hampered by Achilles' problems this season, went down with what appeared to be a lower leg injury early in the second half and limped off the field he came back but left the locker room in a boot.