Everyone marvels at how Ray Lewis has been able to play for 17 years.
But what about the longevity of center Matt Birk?
Birk's getting ready to play his 200th career game Sunday against Dallas.
"What can I say?" asked the modest 15-year veteran. "I'm real lucky, real fortunate to be in good situations and play with a lot of great players who probably made me seem a little better than I am over the years. It's truly a blessing to be able to do this for a long time."
It's tough to say who takes more punishment: a center that bangs into 300-plus pound defensive linemen every single play, or a linebacker who has to fend off blockers and make countless tackles.
Both sides are frequently in the trenches, and particularly susceptible to injuries.
Ravens guard Bobbie Williams has been in the league 13 years and played 156 games, so he knows the challenge of durability in the NFL. Injuries have hampered Williams, and he's been limited to blocking on extra points and field goals this year.
Meanwhile, Birk hasn't missed a start since 2005 – a streak of 101 games that's the longest in the NFL at his position.
Asked for his perspective on Birk's milestone, Williams was almost at a loss for words.
"I'm just trying to fathom it," Williams said. "That's a huge accomplishment. He doesn't look like he's slowing down either. That's pretty awesome, man.
"Matt's been doing his thing for 15 years. I'm only in Year 13 and I'm taking a break so far [this season], so he's widening the gap on me."
Birk attributed his longevity to his work in the offseason and during the season. He's addicted to the gym, and despite being a veteran, he is often a participant in the team's voluntary strength and conditioning program.
He also has used stretching guru, Roger Erickson, since he was 14 years old. Birk credited Erickson, probably more than anybody, with helping him get to and remain in the NFL.
"You do all the hard work in the offseason and in-season so you can play on Sundays," Birk said. "That's the payoff for us, the fun part. To be able to do it 200 times is pretty cool."
Birk's climbing up the charts on all-time games played, but he's got a way to go to get to the top.
The all-time leader is kicker Morten Anderson at 382 games. Legendary wide receiver Jerry Rice leads all non-specialists with 303 games. The offensive lineman with the most is Bruce Matthews, who played 296 games in 19 seasons.
Lewis is ahead of Birk with 227 games played. Former Raven Matt Stover played in 297.
Birk didn't know about the milestone, nor did his coaches or teammates.
"Matt kept that a secret," Head Coach John Harbaugh joked. "Well we're just going to have to have a little party. Obviously, Matt didn't want us drawing attention to that. So, since that's the case, we'll make sure we give it our full attention."