Head coach Marvin Lewis, who has a short week of preparation following Sunday's emotional win over the Steelers, said his team will be ready regardless of who's behind center.
"We have to prepare for the Browns offense," Lewis said. "If Johnny Manziel is the quarterback, we played him last year. We've seen he's had some opportunity this year in the regular season. Our guys will be aware of that, and we have to adjust on the fly."
In last season's meeting at FirstEnergy Stadium, Manziel was sacked three times and pestered often while passing for only 80 yards and two interceptions in a 30-0 loss.
McCown played Sunday's game against Arizona with sore ribs which as of Tuesday were making it difficult for him to sleep.
Still, head coach Mike Pettine said both quarterbacks will be prepared to play on Thursday.
If he's the starter Thursday night, Manziel won't be the only quarterback on the field looking to atone for a horrific performance.
In last season's matchup with Cleveland on Thursday Night Football, Bengals quarterback Andy Dalton went 10 of 33 for 86 yards and three interceptions for a dismal 2.8 passer rating in a crushing 24-3 loss at home.
"I have to put that behind me," Dalton said earlier this week. "I think it was a one-time thing. You can't let anything like that creep into your head. I think it will be compared to last year, just because it was a Thursday night game against Cleveland. But, we are in a much better place this year."
Dalton is playing at a much higher level too, helping the Bengals improve to 7-0 for the first time in franchise history with a 16-10 win on Sunday in Pittsburgh.
Cincinnati holds a commanding three-game lead in the AFC North and are five and one-half games ahead of Cleveland.
In addition to McCown, the Browns also will likely be without strong safety Donte Whitner and cornerback Joe Haden on Thursday night.
"We struggled and didn't play very well," said Lewis of last year's loss to Cleveland. "After that, we righted our course. This is a big football game. It's a division game, it's at home, and our people will be loud. It's a very important game for us. Right now, we have two wins in the division, this would be our third win, and we will be half way through the division and holding serve."
SERIES HISTORY: 84th regular-season meeting: Bengals lead series. 44-39 after splitting the two meetings last season. The series has been dominated by the home team which has gone 51-32 all-time.
--Bengals head coach Marvin Lewis said his team is preparing for Cleveland's offense rather than focusing on whether Josh McCown or Johnny Manziel is the Browns' starting quarterback. But, the skill sets are decidedly different. The Bengals pressured Manziel early and often in last year's 30-0 win in Cleveland. Without strong safety Donte Whitner and corner Joe Haden likely out, look for Bengals QB Andy Dalton to put pressure on the Browns' secondary. Despite a short week to prepare, Cincinnati will be highly motivated after last year's humbling 24-3 loss to Cleveland on "Thursday Night Football" which featured the worst performance of Dalton's career.
MATCHUPS TO WATCH
--Bengals WR A.J. Green vs. Browns CB Johnson Bademosi and a depleted Browns secondary.
Typically a Browns-Bengals matchup would feature a four-quarter war between cornerback Joe Haden and Green. But, with Haden in concussion protocol and unlikely to play, Bademosi, a fourth-year player out of Stanford, likely will make his first career start against Green, Marvin Jones and a versatile Bengals receiving corps.
--Browns QB Johnny Manziel vs. Bengals defense.
If Manziel indeed starts in place of injured Josh McCown, it will be his chance to show how much he's improved since Dec. 4, 2014 when he passed for only 80 yards, threw two interceptions and was sacked three times in a 30-0 loss to the Bengals. During that game, Bengals defensive players mocked Manziel's "money sign." Manziel has shown flashes of ability this season, but will be tested by Cincinnati which ranks third in sack differential.