Ray Lewis is 37. Ed Reed is 33. The critics that argue Baltimore's defense is too old point to these two players' ages, saying time is running out on a Super Bowl run.

Coach John Harbaugh's heard the criticism, and it appears he finds it unfounded. On Friday, The Baltimore Sun's Matt Vensel asked Harbaugh what his reaction is when he hears that.

"Mad as heck," Harbaugh said. "It doesn't make me happy. But then I say, 'What do I care what they think?' It's great to be underestimated. That's a big advantage in life. So hey, spread the word and tell everybody in the world that we're over the hill and that the window's closing and all the cliches they want to use because they can't think of any good articles from guys like you, Matt. We'll take that, we'll take it every time."

To add context, Harbaugh's response wasn't sarcastic or snippy. It was as if he appreciated the question because in some ways that criticism could be construed as unfair.

Haloti Ngata is 28 and in the prime of his career. Lardarius Webb, Cary Williams and Jimmy Smith are all young cornerbacks. Linebacker Jameel McClain's only a five-year veteran and nose tackle Terrence Cody is entering his third season.

In fact, a case could be made the Ravens have gotten younger on defense over the past two seasons.

"I think you always have to do that," Harbaugh said. "You always have to get younger in this league. It's a cycle. Nobody lasts forever. It's a tough game, a hard sport."

Other notes: Webb was excused from practice for a personal matter. He's expected to return to training camp Saturday.

Harbaugh said Ngata's hamstring isn't major. The team will take it slow with his recovery.

In what could end up being an intriguing kicking competition, Billy Cundiff and rookie Justin Tucker made all their field goal tries. Tucker boomed one from 57 yards away and has showcased a lot of power on his attempts.

Linebacker Sergio Kindle had 1.5 sacks and an interception during Friday's practice. Tight end Dennis Pitta and wide receiver Tandon Doss also had solid outings.

Follow Ravens reporter Jason Butt on Twitter: @JasonButtCBS and @CBSSportsNFLBAL.