Since their inception, the Baltimore Ravens have always had a few constants. They've always worn purple, gold and black. They've always had a marching band. And they've always had Ray Lewis.

The second pick in Ravens' history, Lewis has earned nearly every accolade throughout his 17-year career. And at 37, Lewis is stopping the clock by playing at an All-Pro level. When he saw the league turn away from the power run game and move toward a passing league, he adapted. Though he's lost weight and focused on staying in shape off the field, he doesn't believe that makes him any less of a threat.

"Being a big hitter has nothing to do with weight," Lewis told reporters Wednesday. "Being a ferocious hitter has everything to do with your heart. All you have to do is come in there full speed. Some of the greatest hitters of all time were never that big. They just always came with a different thought process when they came, and that's always been my mentality."

At a svelte 250 pounds, Lewis thinks he is more adapted to the modern NFL that involves more dynamic play from running backs and tight ends. It also gives him the opportunity to pad his résumé with more interceptions.

"Anytime you throw the ball as much as people are throwing the ball now, your odds are always going to be high," he said. "You go back to the (Cowboys tight end Jay) Novaceks and the (49ers tight end) Brent Joneses and all those guys, with the West Coast offense and things with him, but nowadays, guys are using tight ends and running backs way more than anything else, and that's why I think linebackers are getting so many opportunities for interceptions because they are throwing the ball over the hashes and a lot of places where linebackers usually roam."

Lewis will need that extra speed Sunday when he goes against quarterback Michael Vick and the Eagles' explosive offense. Though there has been much debate about how Vick should play the game, Lewis isn't listening. He knows the signal-caller is dangerous no matter what.

"Anytime you sit back and watch Michael Vick play the game of football, I just think the toughest Michael Vick is Michael Vick," Lewis said. "And any time he is Michael Vick you have to come in and play him like he's Michael Vick. You can't ask for one or the other. You have to come play him as who he is."

Challenges that are presented from playing teams like the Eagles and chasing a second Super Bowl are what keep Lewis in the NFL. But when he stops feeling that passion, or when his body starts to fail him, he'll know it's time to hang up the cleats.

"If I'm declining and things aren't right, then it's time for me to go," he said. "But if my body is feeling good and I'm not going through a surgery here; a surgery there, and I'm actually putting at risk my health, then it's time for me to make that decision. But when you love the game the way I love it... it's going to always keep you coming back."

While the Ravens certainly look the part of a premier NFL team, the Eagles will be looking to knock them off that track Sunday afternoon in Philadelphia.

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