OWINGS MILLS, Md. (AP) Coming off his worst season as an NFL head coach, John Harbaugh really doesn't know what to expect from the Baltimore Ravens this year.
''Either we're going to be good or we're not,'' he said. ''I have reasons for optimism, and I have reasons for pessimism.''
The Ravens staggered to a 5-11 finish in 2015 after losing quarterback Joe Flacco, running back Justin Forsett, wide receiver Steve Smith and linebacker Terrell Suggs to injury. Harbaugh is still waiting to see what first-round draft pick Breshad Perriman can add to an offense that was without a vertical threat after he tore a knee ligament during his first NFL practice.
If Baltimore is to again become relevant in the AFC North, it must cleanse itself of the misery that defined last season.
''We have to get rid of last year's team, last year's feel and everything that went terrible with last year and leave it back there,'' Suggs said. ''We have to be the Ravens that we know we are supposed to be, that we are accustomed to being. That is definitely the No. 1 thing on our list as a motivator.''
Back in the days when Ray Lewis roamed the middle of the field and Ed Reed deftly monitored passes deep into the secondary, the Ravens were a defensive force. To become a contender again, Baltimore must improve a unit that last year surrendered 401 points, including 103 in the fourth quarter. Thus, the Ravens lost nine games by eight points or fewer.
The addition of free agent safety Eric Weddle should help, as should the return of Suggs.
''I really feel good about this defense. I did last year, too. We just had a rash of injuries,'' defensive coordinator Dean Pees said. ''I feel like we're maybe a little faster than we were a year ago. We're going to need to be. I'm very optimistic.''
Here are some things that need to go right for the Ravens in 2016:
FLACCO'S HEALTH: The Ravens' success depends heavily on Flacco, the franchise leader in completions, passing yardage, touchdown passes and 300-yard games. Before tearing the ACL and MCL in his left knee on Nov. 22, Flacco started in 137 straight games (including playoffs).
Flacco acknowledged that he's not back to 100 percent, but his arm is sound.
''He's still elite,'' tight end Crockett Gillmore said.
The Ravens provided Flacco with two additional targets during the offseason, signing free agent wide receiver Mike Wallace and tight end Benjamin Watson. But Watson was lost for the year when he tore his Achilles tendon in the third preseason game.
RUNNING BACK SHUFFLE: The most surprising final cut last week was Forsett, who was a Pro Bowl alternate two years ago after rushing for 1,266 yards. But he was re-signed Monday and joins a mix that begins with Terrance West and includes Javorius Allen and rookie Kenneth Dixon, who injured his knee in the preseason.
West has started only six games over two seasons and is still 96 yards short of reaching 1,000 for his career.
ROOKIE LINEMEN: The Ravens thought they had a fixture at left tackle when they signed Eugene Monroe to a long-term contract. Unfortunately, the oft-injured Monroe turned out to be a bust and was released.
Top draft pick Ronnie Stanley has stepped into a starting role, and now it's up to him to protect Flacco's blind side.
''That is an important spot, obviously,'' offensive coordinator Marc Trestman said. ''There is nothing that tells you he can't do this, and the game is not going to be too big for him.''
Baltimore will also employ rookie guard Alex Lewis, sometimes in tandem with Stanley on the left side of the line.
(DEFENSIVE) BACKFIELD IN MOTION: Weddle was the most important free agent pickup of the offseason. A three-time Pro Bowl selection with San Diego, he had 104 tackles in 2014 and 75 a year ago before going on injured reserve in December.
Former cornerback Lardarius Webb moves to free safety, which caters to his speed. Jimmy Smith is solid at one of the corners, but Shareece Wright must improve on the other side for the Ravens to be an effective pass defense.
The key is chemistry.
''It's just a guy getting used to working with other guys, how they verbalize, how they think, how they communicate and how they talk,'' Pees said.
KICKING IT: The Ravens signed kicker Justin Tucker to a whopping $16.8 million, four-year contract in July.
Tucker is the second-most accurate kicker in NFL history, making 87.8 percent of his field goal attempts. He's never missed a conversion and last year scored 128 of the team's 328 points.
''Justin has become a cornerstone of our team,'' general manager Ozzie Newsome said.
The Ravens also have 2015 Pro Bowl punter Sam Koch and long-snapper Morgan Cox back.
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