OWINGS MILLS, Md. — Rookie quarterback Joe Flacco will start in the season opener Sunday for the Baltimore Ravens, who awarded the job to their top draft pick because he's the healthiest player at the position.

Flacco, the 18th pick overall, will launch his NFL career against the Cincinnati Bengals. There is a chance the two other quarterbacks competing for the job, Troy Smith and Kyle Boller, both will not be available as backups.

"It wouldn't be realistic to have one of those two guys as a starter, for sure. If they can back up, I think that would be an upset," coach John Harbaugh said Monday.

Smith is still feeling the effects of infected tonsils and Boller has a sore shoulder that could ultimately require surgery. In an effort to add depth, the Ravens worked out quarterbacks Chris Simms, Joey Harrington and Todd Bouman on Monday.

"We need a backup quarterback for the game," Harbaugh said.

But for now, the focus is on Flacco, who was labeled the team's "quarterback of the future" by general manager Ozzie Newsome on draft day shortly after the Ravens traded up to get the former University of Delaware standout.

Well, the quarterback of the future is now the quarterback of the present.

"This is what I wanted all along," Flacco said. "Things happen funny. I've gotten my opportunity, and now it's up to me to go out there and play."

After two preseason games, Harbaugh essentially eliminated Flacco in what began as a three-way competition to be Baltimore's starting quarterback. The plan was to start Smith in the third game, against the St. Louis Rams, then take a look at Boller.

But neither Smith nor Boller was available to play against the Rams or the preseason finale against Atlanta. Flacco started both games and played well enough to maintain the role in the opener.

"If one of you guys wrote this in a movie script, no one would believe it," Harbaugh said.

Flacco went 35-for-67 for 284 yards and no interceptions during the preseason. His quarterback rating was better than that of Boller or Smith, and he threw Baltimore's lone touchdown pass.

Now, however, it's for real. If he plays well, Flacco might be able to keep the job. But that's not what motivates him.

"The thinking is to win some games. That's the first thing I'm thinking about and the only thing I'm thinking about," the 6-foot-6 rookie said.

The Ravens probably would have preferred to let the 23-year-old Flacco learn from the sideline before thrusting him into a game that counts. But the way the situation played out, that wasn't an option.

"To me, it doesn't even matter. Joe's our guy. We think he can win for us," Harbaugh said. "He had a heck of a practice, and we're excited to go out there and play with him."

Smith, meanwhile, was just glad to be back with his teammates. He may not be able to practice this week, but at least he can be surrounded by friends in the locker room.

"I'm not thinking about starting at all. My health comes first in any situation, and then my team comes," he said. "Just being back around the guys, laughing and joking and being a part of something special here, is what's most important."