The experiment was met with poor results as Boller struggled immediately and hasn't emerged as a consistent passer in subsequent seasons, losing his starting job a few years ago to a since-retired Steve McNair.
Five years later, the Ravens may have to roll the dice again. With Boller dealing with a serious shoulder injury and Troy Smith hospitalized with a tonsil infection, Flacco may have to start the season-opener Sept. 7 against the Cincinnati Bengals.
He disputed the notion that it would be best for his progression to watch from the sidelines when the season starts.
"How are you going to learn when you're sitting?" Flacco said. "You learn a lot of different ways, but, for me, the best way to learn is to go out there and experience it for yourself."
Since the first preseason game where he was incomplete on three passes and lost a fumble, Flacco has improved steadily.
He completed 8 of 13 passes for 72 yards and no interceptions in a 10-9 loss to the Atlanta Falcons in a preseason finale, outshining fellow first-round pick Matt Ryan.
Although Flacco was supposedly eliminated from the competition weeks ago, he is back in the picture due to the other quarterbacks' medical problems.
"I don't worry about that, the coaches worry about that," Flacco said. "All I can do is go out and practice every day and act like I'm a starter and go out there on the field and play like I am. I think I've done a pretty good job."
For the preseason, Flacco has completed 36 of 68 passes for 298 yards, no interceptions and a team-high 69.4 quarterback rating. He has thrown the Ravens' lone touchdown pass.
Boller is out indefinitely, and it's unclear if Smith will recover in time to overtake Flacco.
"It would seem like Joe would be more likely to get the opportunity, I wouldn't be that surprised," wide receiver Derrick Mason said. "If Joe is our only healthy quarterback, then he's going to have to play. If he's the only option, I would imagine he's going to be the guy."
Smith was on the verge of being named the starter when he became ill prior to a scheduled start against the St. Louis Rams.
"It was very unfortunate for Troy ," center Jason Brown said. "It looked as though he was about to get that nod."
The former Heisman Trophy winner hasn't been ruled out by the coaching staff yet, though. Smith has lost 13 pounds due to the illness and hasn't been able to practice.
"We had a quarterback who very well could have been our starter miss all that time, so we'll kind of have to factor that into the equation as we go forward," coach John Harbaugh said. "But by the same token, he's had a lot of reps from the very first minicamp on through. So, he knows our offense."
Flacco has gotten better each week with his confidence growing with each snap. The speed of the game has been his biggest challenge, and he has been sacked a team-high six times.
"I think Joe is in a place where he can compete for us as the opening-day starter," Harbaugh said. "Now whether that's the best thing for us, we'll have to see in the next four or five days. But he's handled himself well."
ROSTER CUTDOWN: The Ravens have until tonight at 6 p.m. to cut 22 players to get down to a league limit of 53 players, but plan to make an announcement in the afternoon after informing the players of the bad news.
It creates a lot of tension for players on the bubble heading into today with rookies and first-year players scheduled to come to the training complex for a meeting.
"My mentality is that I'm always on the edge," linebacker Gary Stills said. "The bottom line is you can never do enough. No matter what happens, you appreciate the opportunity. Whatever decision they make, I know that I gave it everything I had. That's how you can live with yourself and look yourself in the mirror as a man.
"If they judge that Gary Stills is no longer a part of this team, then so be it. It won't change how I feel about this team and how I feel about myself as a man and as a football player. This is what life is about."
Rookie seventh-round running back Allen Patrick rushed for 39 yards on 15 carries in the preseason, catching three passes for 31 yards. However, the Ravens may opt to just keep tailbacks Willis McGahee and Ray Rice and fullbacks Lorenzo Neal and Le'Ron McClain with McClain doubling as a 260-pound running back.
"I put my best foot forward," Patrick said. "I gave them everything I had."
Added wide receiver Justin Harper, a seventh-round pick from Virginia Tech who caught one pass for 18 yards: "You know that it's coming down, and you just put it in God's hands and pray that you have earned a spot on this roster."
Competing tackles J'Vonne Parker and Amon Gordon are hoping the Ravens feel a need to keep a sixth defensive lineman.
"It's out of my hands now," Parker said. "All you can do at this point is pray and hope that you did enough to prove yourself."
INJURY REPORT: Cornerback Derrick Martin has his fingers crossed that he won't be placed on injured reserve as his injured right shoulder is improving. He is out of a sling, but missed the Ravens' final two preseason games.
Martin aggravated the sutures in his surgically-repaired shoulder against the Minnesota Vikings, a game where he returned an interception for a touchdown.
"The swelling went down, it's getting better," Martin said. "I should be back probably in the next couple of weeks. I don't know what they're thinking, but I'm hoping to stay on the active roster. I want to play."
Meanwhile, cornerback Samari Rolle (left leg) said he didn't feel well and that's why he didn't play against the Falcons.
"I'm okay now, it was basically the same thing that bothered me during camp," Rolle said. "I'll be ready for Cincinnati ."
BRAMLET'S TRAVELS: Quarterback Casey Bramlet only had a few hours of preparation after being claimed off waivers, catching a red-eye flight from California and going through an impromptu walkthrough at a hotel ballroom prior to kickoff.
He completed 7 of 21 passes for 100 yards and two interceptions, engineering two scoring drives.
"You can learn the snap count, that's about it," Bramlet said. "You can't get any read on your receivers. Coming into this game, I found a couple of guys I thought I might be playing with to run some routes before kickoff just to get a feel."
It helped that Bramlet is familiar with offensive coordinator Cam Cameron's system having played for him last season with the Miami Dolphins prior to being cut this week by the San Diego Chargers.
"I probably wouldn't have been able to do that without having some familiarity with the offense," Bramlet said. "There have been a few offenses in my head. I think the only one I knew on the team was Derrick Martin, who I played with at Wyoming . It's been a crazy ride."
QUICK HITS: This game marked the first time this preseason that the entire offensive line was playing together with the return of left tackle Jared Gaither, something that offensive line coach John Matsko has been waiting a long time for. Flacco wasn't sacked. "Coach Matsko demands a lot out of all of us, and he had us ready to go," right tackle Adam Terry said. "He's a taskmaster. Our goal was to play physical. We still have to clean some things up, but, as a whole, I don't think there was a lot of pressure on the quarterback and we moved the ball." ... Defensive end Marques Douglas played after being acquired in a trade from the Tampa Bay Buccaneers and recalled many of defensive coordinator Rex Ryan's schemes from his stint as a starter here prior to signing with the San Francisco 49ers four years ago. "Some memories came back," Douglas said. "I received a few love taps from the Atlanta Falcons. Being back with the guys, it's exciting."
Aaron Wilson covers the Baltimore Ravens for the Carroll County Times and the Annapolis Capital.
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