The Ravens weren't alone in getting off to a troubling start to the season following their 49-27 blowout loss to the Denver Broncos in which Peyton Manning tied an NFL record with seven touchdown passes.
Every AFC North division team is winless following their first game.
The Pittburgh Steelers' 16-9 loss to the Tennessee Titans was also marked by season-ending injuries to three key players.
Pro Bowl center Maurkice Pouncey is out for the season with a torn anterior cruciate ligament, linebacker Larry Foote is out for the year with a biceps injury and running back La'Rod Stephens-Howling is out for the season with a torn anterior cruciate ligament.
The Steelers are bringing back running back Jonathan Dwyer after rushing for just 32 yards on 15 carries as quarterback Ben Roethlisberger was sacked five times.
The Cincinnati Bengals had a narrow loss to the Chicago Bears, falling 24-21. They collapsed after building a lead as the Bears scored the final 14 points of the game, intercepting Bengals quarterback Andy Dalton twice overall.
The game-winning touchdown was scored by Bears star wide receiver Brandon Marshall, who finished with eight receptions for 104 yards. The Bengals at least had some decent moments as wide receiver A.J. Green led them with nine receptions for 162 yards and two touchdowns.
The Cleveland Browns' 23-10 loss to the Miami Dolphins was marred by quarterback Brandon Weeden throwing three interceptions as running back Trent Richardson was held to 47 rushing yards. Weeden was sacked six times as Cameron Wake had a game-high 2.5 sacks.