His 62 wins over the last 5 years, including those eight in the postseason, are the most by any quarterback in the league.
Now, as for what Flacco isn't, he isn't an elite quarterback. At least not yet.
I'm not saying that to disparage the Audubon, N.J., native. I believe he's one of the league's better quarterbacks, which he has clearly proved in these playoffs, compiling a 114.7 passer rating, averaging 9.2 yards per attempt and throwing eight touchdown passes and no interceptions in 93 pass attempts to help put his team 60 minutes from the Lombardi Trophy.
But "elite" is rarified air. The Merriam-Webster Dictionary defines elite as "the choice part; the best of a class."
In my mind at least, there really are only four "elite" quarterbacks in the league right now: Brady, Peyton Manning, Drew Brees and Aaron Rodgers.
The Giants' Eli Manning has won two Super Bowls. But he also has a .586 career completion percentage and an 82.7 career passer rating. Very good? Yes. One of the league's 10 best quarterbacks? Most definitely. Elite? No. Same with Flacco. Same with Matt Ryan. For now.
"I think Joe is a little underrated," said ESPN analyst Trent Dilfer, who was the quarterback on the Ravens' 2000 Super Bowl-winning team. "But I don't use this 'elite' label very often. There's definitely four or five guys in the league that have kind of a seat at the table of greatness. That's kind of an elite table, if you want to say it.
"I'd say Joe and Matt Ryan and some of these other guys are at the next table. They're excellent. They're very, very good players.
"I think Joe drives a lot of what [the Ravens] do. And when they're successful, a lot of it is because he's successful and he's making plays that are kind of outside the scheme."
Flacco insists he doesn't care what people think of him. But every time he says it, you become more convinced than ever that he does care. Probably more than he should.
It's kind of like Donovan McNabb and the whole draft-day booing thing. He always said it was no big deal. But years later, he still would cringe at the mere mention of it.
"I really don't care," Flacco said the other day. "There are guys out there that have got to make a living hating on somebody. If that's going to be us, if that's going to be me, then I plan on being around for a while. And if you want to continue to do it, I'll be here."
Even this week, Flacco, a prototypical pocket passer, finds himself playing second fiddle to the flavor of the week - the 49ers' Colin Kaepernick, a quarterback with just nine career starts, whose ability to run as well as throw the football has captured everyone's attention.
Reminds me of the time years ago when an Eagles beat writer asked Ron Jaworski if he wished he had Joe Theismann's legs. It's the one and only time in Jaworski's career that he cut an interview short.
"I'm so glad we're going to the Super Bowl right now so people can get off Joe's back," Ravens wide receiver Torrey Smith said. "Because he led us there."
There is no disputing that. After an up-and-down regular season that saw him finish 12th in the league in passing (87.1) and 19th in completion percentage (59.7) and throw just 22 touchdown passes, he has taken his game to another level in these playoffs.
In the last two games, he has prevailed over two of the QB Elite, throwing for 331 yards and three touchdowns in the Ravens' overtime win over Manning and the Broncos, and then leading a second-half surge that took down Brady and the Patriots in the AFC Championship Game.
After completing just six of 12 passes for 81 yards and no touchdowns in the first half against the Patriots, Flacco put on his Superman cape and was 15-for-24 for 159 yards and three TDs in the second half as the Ravens won going away.
"You're seeing some good output, obviously, from him in terms of production," Ravens coach John Harbaugh said. "That's really good to see, but Joe has had that before. To string it together like he's done back-to-back-to-back in the most critical time of the year is the great thing about it.
"He's come a long way, but he's come the way that you would expect any quarterback to develop. It's in his fifth year, and to see it happen like this is something that we kind of planned for. But it's also a great thing to see."
The Ravens have converted their last eight red-zone opportunities into touchdowns, going back to the second quarter of their wild-card win over the Colts. In those five red-zone trips, Flacco has completed nine of 11 passes, five for touchdowns.
Flacco's .544 playoff completion percentage isn't very good and neither is his third-down completion percentage (.346). But he has made the big plays when he has needed them. The biggest throw of his career - his 70-yard touchdown heave to Jacoby Jones that sent the Denver game into overtime - came on third-and-3.
Harbaugh and offensive coordinator Jim Caldwell have let Flacco take advantage of the game's strongest arm during the playoffs.
During the regular season, Flacco attempted just 92 passes that traveled 20 or more yards in the air, and completed 25. In the Ravens' three playoff wins, he is 12-for-24 on throws of 20-plus yards, including 9-for-13 against the Colts and Broncos.
Before the divisional-round game against the Broncos, Ravens linebacker Ray Lewis, who will retire after Sunday's game, told Flacco that it was his time for him to take over as the team's leader.
"I knew for us to go in there and win that particular game that Joe had to play exceptionally well, which he did," Lewis said. "To pass that along to him is whatever it is.
"Who knows who turns into that next leader here? There are a lot of guys that can definitely step into that role. But I think Joe has a great advantage and head start to really becoming that next true, true leader. He has to come out of his quiet shell a little bit, but outside of that, Joe is definitely a great candidate for it."
Flacco is more Joe Cool than Joe Rah-Rah. His personality doesn't lend itself to fiery speeches or getting in teammates' faces. And he's not sure that's really necessary.
"There are a lot of different ways to lead," he said. "The bottom line is it's about motivating your players to get the best out of them and having the belief that you can go do it in any situation.
"Ray does a great job of that in his own way, and I don't know if there's anybody quite like him in that category. So, in an effort to do something along the lines of the way he does it would be a mistake, just because I don't think you're going to live up to it.
"You've got to do it your own way, and I think as you get more comfortable with people, and people understand you more, and you become more confident in them, and they become more confident in you, you become more vocal as times goes on."
On Twitter: @Pdomo