As the class of quarterback crop in the 2008 draft -- they were the only two taken in the first round that year -- they broke into the league together. They both became starters as rookies and have remained that.
But now nearly halfway through this, their fifth season, only one of them is making a strong push into the discussion of the game's elite quarterbacks, and it isn't Flacco.
Going into this season, their regular-season records were remarkably similar; Flacco was 44-20 and had started every game played by the Ravens since he was drafted. Ryan was 43-19 and had started all but two games he missed in 2009 with a turf toe injury.
The one trump card for Flacco, where he holds an indisputable edge over Ryan, has been playoff experience. Flacco has led the Ravens to the playoffs all four seasons -- the first starting quarterback since the 1970 merger to accomplish that -- and has won at least one playoff game every year. His overall playoff record stands at 5-4. Last season, he outplayed Tom Brady in the AFC title game and basically threw a perfect pass to Lee Evans that should have put the Ravens in the Super Bowl.
Ryan, on the other hand, has yet to win a playoff game. He's 0-3 in the playoffs, including the Falcons' 24-2 loss to the Giants last season.
Flacco came into this season off his best training camp and working in an offense designed to showcase his talents. But he remains inconsistent, impressive at home and very ordinary on the road. Ryan, on the other hand, has led the Falcons to the league's only perfect (6-0) record, including 3-0 on the road.
Ryan ranks fourth in the league in quarterback rating this year at 98.8. He is also fourth in touchdown passes (14) and fifth in completion percentage (.678). Flacco ranks 20th in quarterback rating (84.0), 23rd in completion percentage (.595) and 13th in touchdown passes (9).
If the season ended tomorrow, Ryan might be the league's MVP. Of course, it doesn't end tomorrow. There is still more than half the season to play. Plus, Ryan and the Falcons have been here before; in 2010, he led them to a 12-2 start and a No. 1 seeding in the playoffs, but then the Falcons were trounced by Green Bay, 48-21, in the divisional round.
Until Ryan shows he can win a playoff game, he will always be dogged by the zero after his name when mentioning playoff wins.
But for now , the Flacco-Ryan debate has swung significantly in Ryan's favor.