Derek Carr took the apart the Ravens defense in back-to-back seasons, throwing for 550 yards and seven touchdown passes in Oakland Raiders' victories in 2015 and 2016.
However, the Ravens won't have to deal with the standout quarterback Sunday.
Raiders coach Jack Del Rio announced Monday that Carr, a Pro Bowl selection the past two years, has a transverse process fracture in his back and will miss at least two weeks, if not longer.
The Ravens go on the road to face the Raiders Sunday in a matchup between teams that have both lost two straight games.
With Carr out, the Raiders are expected to turn to veteran backup EJ Manuel. The former Buffalo Bills quarterback relieved Carr, who hurt his back on a sack in the second half of Sunday's loss to the Denver Broncos, and went 11-of-17 for 106 yards and an interception.
When he spoke to reporters at 4 p.m. Monday, Ravens coach John Harbaugh was operating under the assumption that Carr would play Sunday. The initial reporters were that he was just dealing with back spasms.
However, an X-ray taken on Carr Monday revealed the fracture.
"I think the thing that we have seen in watching EJ Manuel is he's running the same offense that Derek Carr was running. It's not like they have a different offense for Manuel. He's running the Oakland Raider offense," Harbaugh said. "We'll prepare for their offense with an understanding of what he does well. They're both mobile. Derek Carr can really run, too. It's not like we're talking about two guys who aren't mobile. They're both mobile quarterbacks."
Manuel, 27, was a first-round pick of the Bills in 2013. He started 17 games for them in parts of four seasons and went 6-11 as a starter. For his career, the 6-foot-5 and 237-pound signal caller has a .585 completion percentage and has thrown 19 touchdown passes and 16 interceptions in 29 games.
He did help lead the Bills to a 23-20 victory over the Ravens as a rookie in 2013. In that game, Manuel completed 10 of 22 passes for 167 yards, one touchdown and two interceptions.