The Ravens said goodbye to a lot of years of experience and special memories in parting ways this offseason with the likes of Todd Heap, Derrick Mason and Kelly Gregg.

But that could be a good thing — or at the very least, an advantage early in the 2011 season.

The Ravens have turned over nearly half of team, adding 20 new faces to their 53-man roster. Ravens fans won't be the only ones reaching for their rosters during Sunday's season opener against the Pittsburgh Steelers.

"As I sit here today, I am probably a little bit more uneasy than I normally am when we play these guys, because they have so many new guys that we have to account for," Steelers coach Mike Tomlin said. "I think that's something that needs to be stated up front about this. They probably know more about us than we know about them."

The Ravens aren't the only playoff teams overhauling the roster. The New England Patriots have 17 new players, and the defending Super Bowl champion Green Bay Packers have 16.

Change has been a constant theme this summer for the Ravens. It seemed like every week brought a new starter onto the team.

On Aug. 2, the fourth day of training camp, the Ravens agreed in principle with All-Pro fullback Vonta Leach. On Aug. 12, the day after the preseason opener, they traded a fourth-round draft pick to Buffalo for speedy wide receiver Lee Evans. On Aug. 24, a day before the third preseason game, they signed mammoth offensive tackle Bryant McKinnie.

That's in addition to the Ravens' entire draft class — from first-rounder Jimmy Smith to seventh-rounder Anthony Allen — making the team. In total, there could be as many as eight new starters lining up against the Steelers: Evans, Leach, McKinnie, tight end Ed Dickson, nose tackle Terrence Cody, cornerbacks Smith and Cary Williams and safety Tom Zbikowski.

While the Ravens have undergone change, Pittsburgh maintained continuity. The Steelers, the oldest team in the NFL, added seven players to their Super Bowl runners-up roster.

They have one new starter (right guard Doug Legursky) and return all their starters to the NFL's No. 2 defense.

"You can look at it for them and say, 'Keeping their core together is an advantage for them,'" Ravens linebacker Ray Lewis said. "And then you can come on the flip side for us and say, 'The different changes we did make, we didn't make changes to get worse, we made changes to get better.'"

jamison.hensley@baltsun.com

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