The Ravens' secondary is among the NFL's best, with the likes of Ed Reed, Bernard Pollard, Lardarius Webb and Cary Williams.
A.J. Green of the Cincinnati Bengals was held to 70 yards on five receptions. And though Philadelphia Eagles quarterback Michael Vick passed for 371 yards, his blazing-fast receiving corp of DeSean Jackson and Jeremy Maclin combined for nine catches and 137 yards.
The problems in the pass coverage for the Ravens, however, have come underneath. They have a seasoned linebacker in Ray Lewis, 37, but relative neophytes in Courtney Upshaw (rookie), Albert McClellan (second season), Jameel McClain (fifth) and Paul Kruger (fourth).
Eagles tight end Brent Celek had eight receptions for a career-high 157 yards, almost 20 yards per catch, in their 24-23 victory.
The Ravens chalk up the failure to the secondary and linebackers not communicating properly in their zones.
It was Upshaw's first start as he filled in for Kruger, who was out with a back injury.
"He had some good pass rushes. He had some hits on the quarterback," defensive coordinator Dean Pees said of Upshaw. "He has to just keep learning the system, knowing he pass drops. That is what usually always the outside 'backer's biggest learning curve is all the pass drops because they haven't had to do it in college."
McClellan had the best chance at a game-changing play in the third quarter when Vick hit him in his hands with what should've been an easy interception. Instead, McClellan couldn't grasp it as the Eagles were able to kick a field goal to tie the score at 17.
On Philadelphia's game-winning drive, Celek had catches of 24 and 13 yards to set up Vick's one-yard touchdown run.