Updated

ORCHARD PARK, N.Y. (AP) -- Andy Dalton threw three touchdown passes and the unbeaten Cincinnati Bengals won their sixth straight to match the team's best start to a season with a 34-21 victory over the Buffalo Bills on Sunday.

With star receiver A.J. Green covered much of the game, Dalton completed touchdown passes to Marvin Jones, Tyler Eifert and Jeremy Hill. Dalton finished 22 of 33 for 243 yards for Cincinnati, which was also 6-0 to start the 1975 and `88 seasons.

The Bengals broke the game open by scoring 17 points on their first three second-half possessions to build a 34-14 lead.

The Bills (3-3) were undone by injuries and several penalties that allowed the Bengals to enjoy an average drive start of midfield in the first half.

Backup quarterback EJ Manuel started in place of Tyrod Taylor, who was sidelined with a sprained left knee. Manuel finished 28 of 42 for 263 yards with a touchdown and interception.