OWINGS MILLS, Md. (AP) As the Baltimore Ravens grind through another training camp practice, Joe Flacco drops back gingerly to throw.
The quarterback has a metal brace wrapped around his left knee and is the only player on the field in a red jersey. He's wearing No. 5, but it might as well read: Do Not Touch.
Flacco was once considered a Baltimore football equivalent to Orioles Hall of Famer Cal Ripken, baseball's Iron Man. Now, however, Flacco is seeking to return from a season-ending injury in November that snapped his run of 137 consecutive starts.
It was one of many injuries that contributed heavily to a dismal 5-11 finish for the Ravens - their first losing season under coach John Harbaugh.
In his previous seven years, Harbaugh compiled a 72-40 record, reached the playoffs six times and won a Super Bowl.
Then came 2015, when everything went awry.
Baltimore placed 20 players on injured reserve, eight of them starters. The downward spiral began on the first day of training camp, when top draft pick Breshad Perriman tore a knee ligament. The speedy wide receiver was supposed to fill the void left by the departure of free agent Torrey Smith, but Perriman never played a minute and remains in recovery mode with the Sept. 11 opener against Buffalo less than a month away.
Flacco and running back Justin Forsett (broken arm) are back on the practice field, but neither played in Baltimore's preseason opener Thursday night.
The wait remains for Perriman, wide receiver Steve Smith (torn Achilles tendon), and linebackers Terrell Suggs (torn Achilles tendon) and Elvis Dumervil (foot). All four are on the physically unable to perform list and have been rarely seen this summer, even on the sidelines.
''They all want to play, I know that,'' Harbaugh said this week. ''They're all working really hard to play in the preseason, but we're certainly expecting them all back for the opener. We'll just have to make some decisions. Terrell Suggs is the closest. He had the injury the soonest. He's already on me about practice, and I'm holding him back right now. He'll be out there soon practicing. How much we play him remains to be seen. The other guys are probably a little longer away than he is - him being ready - but we'll just see where we go.''
There's also the matter of tight end Dennis Pitta, who had his season end in 2013 and 2014 with a serious hip injury. Pitta missed all last year and is attempting another comeback, but his bid was stalled by a sprained finger he received during a training camp scuffle.
If it isn't one thing, it's another.
Third-round draft pick Bronson Kaufusi, a promising defensive end, broke his ankle in a low-contact drill and will miss the entire season.
''That's a part of the game; it's a part of football,'' Harbaugh said with a shrug. ''It happens for a reason, in my opinion. You have to look at it that way.''
At least the Ravens have Flacco, who spent countless hours rehabilitating his knee to be ready for the start of training camp. Baltimore used three starting quarterbacks in his absence last year, none of whom came close to serving as an adequate alternative to the franchise leader in completions, touchdown throws and yards passing.
''Obviously, last season, what he went through - what a lot of guys went through - to have him back and leading this team says a lot about his character, his toughness and why he's one of the best,'' said safety Eric Weddle, arguably the most significant of Baltimore's offseason free agent pickups.
Until Smith and Perriman join the mix, it's uncertain who Flacco will be targeting on the outside. Newcomer Mike Wallace appears to be the most viable option, but he knows he can't go it alone.
''I can't wait until they get back, because I just want to see our group in full,'' Wallace said. ''I think we can be dangerous.''
Being healthy would be good enough.
''I think you always want to play at full strength,'' Flacco said. ''But in the NFL, that's not a reality. You go out there, you play your best, and do your best with what you've got.''
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