1) The Ravens can't be a good team if they can't put away lousy opponents at home.
Just a few years ago, the Ravens were one of the surest bets in the NFL when playing a poor team at home. Stick that opponent with a rookie quarterback, and John Harbaugh's crew was unbeatable.
That era is over.
If we had any doubt, the Ravens screamed it out in bold letters on Sunday. They did their best to lose to the lowly Bears in regulation. Then they lost to them again after a miraculous special teams performance pushed the game into overtime.
A team with playoff aspirations should not need two return touchdowns to defend its home turf against a 1-4 opponent coming to town with the league's 27th best offense. And those two return touchdowns, weird and spectacular as they were, still didn't do the trick.
So it goes when you're stuck with an offense that hands away points with fumbles and botched catches, that can't capitalize on the stops delivered by a still-solid defense.
Despite a decent effort by quarterback Joe Flacco, the Baltimore offense scored zero touchdowns for itself and served the Bears two scores on a platter.
It was a dispiriting step back after the offense played its best game of the season the previous week in Oakland.
A skeptic could look at the Ravens through six games and say they rode an unrealistic turnover margin to two early wins and beat a Raiders team without its star quarterback. They got smashed by the Jaguars and Steelers, and now they've lost at home to a flat-out bad opponent.
It's impossible to say which team will crawl out of the mediocre AFC North. But the Ravens do not have the resume of a legitimate contender.
2) Breshad Perriman is close to going down as a failed pick.
Perriman's day ended early after he suffered a concussion, something we never want to see happen to any player.
But his play before the injury demonstrated how little progress he's made since the Ravens drafted him in the first round in 2015.
Once revered for his speed, Perriman could not separate from his defender on a deep attempt by Flacco late in the first quarter. Then in the second quarter, he let a pass bounce off his hands and into the arms of Bears cornerback Bryce Callahan, whose 52-yard return set up a Chicago touchdown.
So basically, Perriman is neither a home-run threat nor a receiver who can be trusted in traffic.
Approaching the midpoint of his third season, he has 37 career catches. His 2017 production — four catches on 17 targets for 26 yards — suggests a player closer to being released than becoming a star.
This was a big game for Perriman. With Jeremy Maclin inactive because of a shoulder injury, the Ravens needed him to step forward as an offensive threat.
His failure is the tip of a larger problem: the Ravens' desperate lack of effective receivers.
Mike Wallace showed he can still be a dynamic downfield threat against the Oakland Raiders. But aside from him and a healthy Maclin, who would even make an opposing defensive coordinator think twice in planning for the Baltimore offense?
Flacco actually played fairly well in the first half against the Bears. He threw accurately and confronted pressure without panicking. But over and over, we saw his receivers either mishandle the ball or fail to win man-to-man match-ups with Chicago defenders.
Maybe a Hall of Fame quarterback could overcome that. But it's too much to ask of most players, including Flacco.
3) The Ravens' star safeties gave up the few big plays the Bears made.
Eric Weddle thought he had a perfect angle to strip the ball from Chicago running back Jordan Howard in overtime. If he had completed the play, the Ravens probably would have kicked a field goal and won the game.
Instead, Howard slipped out of Weddle's grasp, ran 53 yards and set up Chicago's game-clinching field goal.
The veteran safety's desire to end the game with one decisive strip was understandable. But afterward, he acknowledged his lapse in judgment and execution.
"It's an unacceptable play. You've got to make the tackle," he said. "I had a good hand on the ball, but you just can't do that in that situation. You've got to get him down. We were playing so well as a defense, and it's unfortunate we lose a game because of that."
Meanwhile, Weddle's friend and running mate, Tony Jefferson, let two different Bears tight ends get by him for easy touchdown catches.
In the second quarter, Jefferson bit on a halfback pass, and Zach Miller ran right by him. Then in the third, Dion Simms beat him without any trickery for a 27-yard score.
Jefferson is one of the best run-stopping safeties in the league, but through six games, we've seen that he's much more vulnerable in downfield coverage. Weddle is banged up and not playing at quite the elite level we saw from him last season.
The Ravens thought they might have the best safety tandem in football coming into the season. Instead, they've had two very good but flawed players on the back end of their defense.
4) The Ravens' difficulties against the run were overstated.
In the postgame locker room, Ravens defenders faced question after question about why they'd let the Bears trample them on the ground.
But going into overtime, they had allowed 159 yards on 47 attempts, just 3.4 yards a carry. Given how little Bears quarterback Mitchell Trubisky accomplished through the air, that performance was perfectly adequate.
Outside linebackers Matthew Judon and Terrell Suggs each stuffed a pair of runs behind the line of scrimmage. Those stops were part of a monster game for Judon, who finished with 12 tackles and two sacks. He's now delivered two excellent performances in a row.
Weddle, Michael Pierce and Patrick Ricard also made tackles in the backfield.
Sure, Weddle's big miss on Howard wiped a lot of that good work away, but it wasn't indicative of a systemic problem with run defense.
5) The wide receivers get the attention, but the Ravens' young tight ends have also disappointed.
Two years ago, the tight-end trio of Nick Boyle, Maxx Williams and Crockett Gillmore seemed essential to the team's future.
Boyle, Williams and Gillmore — not one of them older than 24 at the time — combined for 83 catches in 2015. They've combined for 32 since.
Gillmore is on injured reserve and might never play another snap for the Ravens.
Williams was at the heart of the team's troubles on Sunday, fumbling at the Chicago 20-yard line to squander a likely score. He also hurt his ankle on the play, adding to a string of health woes that have limited him to 21 games in three seasons.
Boyle has not only failed to produce much as a receiver this year, he's struggled as a pass blocker (he drew a holding penalty on Sunday).
The Ravens invested heavily in drafting a quality tight end corps to support Flacco. At this point, they have little to show for it. It's yet another reason their offense remains anemic.
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