Before the Super Bowl, owner Steve Bisciotti expressed confidence that Flacco would be the Ravens' quarterback of the future.
"We've never lost a great, great franchise player from the beginning," Bisciotti said. "I'm just very comfortable that it will get done."
Flacco was a first-round draft pick in 2008 out of Delaware. He's the only quarterback to win a playoff game in each of his first five seasons. He passed Eli Manning for most road victories in the postseason when Baltimore won the AFC championship at New England.
In a league where passing records are set nearly every year and a franchise quarterback has become essential to winning a championship, it's rare for someone to even reach the verge of free agency.
And Flacco said himself after the Super Bowl victory that he expected to be back in Baltimore.
"I'm pretty optimistic, but who knows?" he said. "This is a great organization, I love being here, great city. So I don't anticipate any problems."
AP Sports Writer David Ginsburg in Baltimore contributed to this story.