The player who Ravens general manager Ozzie Newsome made two trades to select with the 18th overall pick in last month's NFL draft practiced for the first time at the team's mandatory minicamp in Owings Mills.
"I'm here to play football," Flacco said. "I'm a first-round draft pick, but I don't look at myself as that. I'm looking at myself as a guy whose coming in here to prove he can play quarterback in the National Football League.
"I am definitely going out there to prove something ... and that these coaches made the right decision. I'm going to take it day by day and hopefully get better with each of these practices."
As expected, Flacco made his share of mistakes, but he also demonstrated the kind of big-time arm and accuracy that helped him go from a relative small-college unknown to a first-round pick in a matter of months.
"I have confidence in my ability," Flacco said. "Obviously things are going to take care of itself. I've got a lot of learning to do and after being here for a day, I can see that. It's been a lot of fun so, and hopefully that will continue."
One throw in particular - a long completion to Mark Clayton, who beat rookie safety Tom Zbikowski - gave a small glimpse of what Newsome and director of college scouting Eric DeCosta saw in picking Flacco as the second quarterback chosen behind Boston College's Matt Ryan.
"A guy who's got great potential," new offensive coordinator Cam Cameron said, when asked about his first impressions of Flacco. "A guy who's got to work at it like all these guys do. But obviously there are a lot of things we love about him."
Said veteran wide receiver Derrick Mason, "He can throw the ball. ... The one he threw to Clayton I think was about 50 yards down the field in the air on target. The way he commanded the huddle with the team that was in there with him, I think that speaks volumes of him."
If there were butterflies, Flacco didn't show them, either during the two-hour workout or during the 10-minute post-practice interrogation from the media.
"You have to go out there and control that," Flacco said in the locker room. "You have to make it as simple as possible. You have to tell yourself that you know what you're doing; you have to go out there and execute and do the best you can."
Flacco is certainly in a potentially uncomfortable situation of being brought in after the sudden retirement of Steve McNair, then being thrust into competition for the starting job with Kyle Boller and Troy Smith.
"I don't know if we necessarily talk about that," Flacco said. "All we're doing is trying to help each other out, mostly they're trying to help me at this point. I don't know really too much about helping them because I'm the guy that needs to be taught."
Not that Flacco is conceding the competition to Boller, a former first-round draft pick who has had an erratic five-year career, or Smith, the former Heisman Trophy winner picked in the fifth round last year who started the final two games after McNair and Boller were hurt.
"I'm going to go out there and practice and prove that I am the best quarterback," Flacco said, without a hint of cockiness. "We have two great quarterbacks here, and we're all going to do what's best for the team."
The throw he made to Clayton didn't seem to faze Flacco, even right after he threw it.
"I'm just moving on to the next play," Flacco said. "The last thing I'm thinking about is the play I just completed because I know this is a new offense for me, and I'm worried about the next play and making sure I know what to do on that play."
If Flacco is a wide-eyed rookie in any regard, it's because he is now teammates with players he used to watch on television.
"It's definitely different to see a Ray Lewis come into the locker room," Flacco said. "I'll get used to that; I don't know if I am right now. It's a lot of fun to go out there and compete with those guys."
Has Lewis said anything to Flacco yet?
"He was just joking around with me, saying that he was going to get a pick off me eventually," Flacco said with a smile. "We'll see."