ORCHARD PARK, N.Y. - After the Bills cut the lead 17-14 at halftime, Bengals quarterback Andy Dalton dug into his bottomless bag of weapons Sunday to produce back-to-back touchdown drives that fueled unbeaten Cincinnati to a 34-21 victory.

With the win the Bengals tied their best start ever with the 6-0 run of the 1975 club that finished 11-3 and the 1988 AFC championship team that went through the regular season at 12-4.

It was Dalton's 22nd career road victory, putting him within two of the record for most ever by a quarterback in his first five seasons since the 1970 merger. His next away win ties him with Dan Marino, Ben Roethlisberger and Matt Ryan and a date looms in Pittsburgh in two weeks against Roethlisberger's Steelers after the bye week.

Dalton finished 22 of 33 for 243 yards with 3 touchdowns and 0 interceptions for a passer rating of 118.6. His favorite target Sunday was Marvin Jones with 9 catches for 95 yards. Jeremy Hill led the ground game with 56 yards on 16 carries.

When Dalton split out tight end Tyler Eifert at the last instant and kept it high for Eifert to pluck it away from safety Bacarri Rambo for a four-yard touchdown with 1:42 left in the third quarter to muffle Ralph Wilson Stadium, the Bengals had scored on all four red-zone possessions and Dalton was 17 of 26 for 207 yards and three touchdown passes for a 128.2 passer rating.

With the Bills defense rolling coverage to Bengals wide receiver A.J. Green, running mate Marvin Jones went off on the first series of the second half with four catches for 66 yards and that included a cart-wheeling 10-yard touchdown on a screen pass that gave the Bengals a 24-14 lead with 10:15 left in the third quarter.

Green finished the first half with one catch on two targets for five yards as Bills head coach Rex Ryan used a variety of looks on him and didn't blitz as much as usual.

Dalton simply went other places as Jones grabbed his career-high ninth catch in the run. The running game also stirred in the second half. Bernard, who had 50 yards on his first eight runs, bulled for a big first down with 5:08 left.  On the first drive of the second half, Dalton uncorked a sky-ball 42-yard bomb down the middle of the field to Marvin Jones in a duel with cornerback Stephon Gilmore and safety Duke Williams. Dalton put it on a dime as Jones somehow made the catch in the middle of those two while looking directly over his head.

Jones then scored a touchdown on a screen from 10 yards out and finished it off in spectacular fashion when Jones put one hand down on the ground and then launched himself over Duke Williams for the TD.

The Bengals dealt with the loss of WILL linebacker Vincent Rey, their defensive signal caller carted off the field with an ankle injury after missing just three snaps all year. (Both ankle injuries to Rey and right end Michael Johnson don't look to keep them out for an extended time.)

With rookie P.J. Dawson replacing Rey, the Bengals forced a punt and then Green surfaced after Dalton found wider receiver Mohamed Sanu for 24 yards over the middle to convert a third-and-seven.

On third-and-eight, Dalton bobbed, weaved, and rope-a-doped trying to find a receiver and got it to Green coming back on rookie cornerback Ronald Darby for a nine-yard gain on the sideline and a first down.

Dalton threw another quick one to Green out of the no huddle for 10 yards and after Bernard skated for 12 yards behind the right side of the line, Dalton went to Eifert to make it 31-14.

They made it 34-14 on Mike Nugent's 39-yard field goal early in the fourth quarter as the Bengals rung up 213 yards on their first 30 snaps of the half. At one point in the fourth quarter, the Bills' average drive start was their own 16.

At that point the Bengals defense was trying to keep the Bills in front of them and running back LeSean McCoy scored from four yards out to make it 34-21 with 6:50 left.

 After suffering just their second three-and-out on a game's first drive in the wake of the Bills' opening touchdown drive, the Bengals responded with 17 straight points but watched the Bills cut the lead to 17-14 at halftime when Manuel hit wide receiver Sammy Watkins for a 23-yard touchdown pass with 17 seconds left.

The Bengals took a 17-7 lead on Nugent's 47-yard field goal with 7:12 left in the first half, but the Bengals let the Bills hang around when Manuel hit all nine of his passes in the last drive for 81 yards.

Even though Bills right tackle Seantrel Henderson left with a concussion, the Bengals didn't amount much of a pass rush in the half's final march. Left end Carlos Dunlap knifed inside on the touchdown play, but it allowed Manuel to break contain, roll out and find Watkins all alone in the end zone when the Bengals lost him on Manuel's scramble.

Watkins had all four of his catches for 48 yards in the drive, but injured his ankle on the TD and didn't return. Buffalo committed five penalties for 63 yards in the half to help give the Bengals a massive edge in field position with their worst start coming from their own 45. Nugent's longest field goal of the season came in the wake of a face-mask call that put the ball on the Buffalo 36.

The Bills did a good job covering Green (one catch on two targets for five yards) with a combination of man coverage from Gilmore with help at times from a safety and on third-and-three Dalton scrambled and threw it away to give Nugent a shot.

The Bengals had a shot to make more hay with the hidden yards, but they did use the short field to get their two touchdowns in the half as Dalton went eight of 14 for 78 yards and a touchdown with a 96.7 passer rating. Often the Bills went to a more conservative Cover Two zone and head coach Rex Ryan didn't blitz as much as usual.

 The first TD aided by, what else, two Bills penalties, turned into Hill's athletic 13-yard touchdown run that tied the game at seven with 3:26 left in the first quarter.

 Then Bernard matched him with a 17-yard touchdown run as the Bengals took a 14-7 lead with 10:19 left in the second quarter.

The go-ahead drive was set up by Bengals defensive lineman Wallace Gilberry and his pursuit of Manuel. Gilberry drew an intentional grounding call to force an end-zone punt and Bernard set up his own touchdown with a 22-yard swing pass.

When the Bills crowded the box on third-and-one from their 17 and moved into a Bears front covering the center and guards, Dalton checked the play and called a power run with Bernard scurrying behind pulling left tackle Andrew Whitworth and left guard Clint Boling.

After the Bills' 15-yard taunting penalty on the first drive, the Bengals continued to lead the NFL in red-zone appearances when Dalton hit tight end Tyler Eifert over the middle in front of safety Corey Graham for a 15-yard gain and then wide receiver Marvin Jones got separation from Gilmore for a nine-yard gain on the sidelines to convert a third-and-four at the Bills 13.

Dalton then hit Hill out of the backfield and Hill did a great job staying in bounds when defensive end IK Enemkpali missed the tackle. He then lined up Gilmore and ran over him for the touchdown.

The Bengals defense got nicked on its first drive, but rebounded to post a three-and-out after punter Kevin Huber pinned them on the 11. Then slot cornerback Darqueze Dennard, playing in place of the injured Leon Hall, came away with his first NFL interception on Manuel's underthrown deep ball as he ran step-for-step with wide receiver Chris Hogan.

The Bengals again had great field position at the Bills 45, but defensive tackle Marcell Dareus blew up a bubble screen to Marvin Jones and Dalton let a third-and-12 shot-gun snap slither through his hands and he had to fall on it to force a punt.

The Bengals defense had a funny half. They had three three-and-outs and pick, but the Bills also had TD drives of 80 and 86 yards.

Right away the Bills hurt them on the big play. Running back LeSean McCoy, who had missed the last two games, was supposed to be less than 100 percent with a nagging hamstring problem. But he jetted outside around the Bengals left end for 33 yards. No one was near him and on the next snap the closest man to tight end Charles Clay down the middle was safety Reggie Nelson but not close enough to stop a 19-yard catch to suddenly put the ball on the Bengals 28

 The numbers coming in said that could happen, but with Manuel? The Bills backup quarterback hadn't thrown a pass in a real game in 54 weeks, but he looked strong taking the Bills 80 yards in 11 plays for his own two-yard touchdown run on a jet sweep to the left just 5:39 into the game.

The Bills came into the game with the second most big plays in the NFL with 26 and the Bengals defense has been giving them up, tied for 12th giving up the most plus-20s with 16. They've also given up the third most of plus-40 with five. McCoy, with 44 yards in that drive had 61 in the half on 11 carries. Manuel was 15 of 20 for 129 yards for a passer rating of 87.3.

Hill had 13 yards on six carries Bernard had 23 on two.

PREGAME NOTES: The Bengals had a 2015 rarity Sunday at Ralph Wilson Stadium when they sat down a regular because of injury. Veteran nickel cornerback Leon Hall (back) went inactive with Darqueze Dennard expected to take his snaps in the slot against the Bills.

As expected, the Bills started backup quarterback EJ Manuel and sat injured starter Tryod Taylor (knee).

The Bengals, who have used the fewest players in the NFL this season with 47, had no other surprises with wide receivers Greg Little and Mario Alford, defensive linemen Marcus Hardison and Margus Hunt, and tight end C.J. Uzomah inactive as they have been all year. The coaches continued to hang with defensive tackle Brandon Thompson and deactivated Pat Sims.

Starting safety George Iloka (ankle) missed one game and Sims (hip) missed a game before Thompson took his spot in the rotation, but other than that and Hall on Sunday, that's been about it. Hall went limited Thursday and Friday after going just 14 snaps in last Sunday's overtime victory over Seattle.

Dennard, the club's first-round pick in 2014, has been scrounging for play time from scrimmage the past two years and after getting 19 snaps against Seattle he's getting some now. The Bengals apparently figure that giving Hall two weeks off (next week is their bye) is best in the big picture.

Also out for the Bills was injured wide receiver Percy Harvin (hip), but Sammy Watkins got the start at the other wide receiver after missing the last two games.