MILWAUKEE — For a team that has gone into each of the past four seasons with the NFL's youngest roster, the Green Bay Packers are getting noticeably gray at a couple of key positions.

That's probably fine for now, but the Packers need to come away from this year's draft with clear-cut successors at offensive tackle and cornerback. Adding an outside linebacker wouldn't hurt, either.

Still, Packers general manager Ted Thompson swears he'll stick to taking the best player available regardless of need.

"I honestly and truly believe that if you get caught up trying to reach for need at all, that's when you make your mistakes," Thompson said. "And I feel like our core team is strong enough that we don't have to search out like that. I know it's what I always say, but I really mean it."

That said, offensive tackles Chad Clifton and Mark Tauscher and cornerbacks Charles Woodson and Al Harris all are in their 30s. Harris is coming off a season-ending knee injury and his availability for the beginning of training camp is unclear. And Packers coach Mike McCarthy has made it clear that having a backup plan behind Clifton is a top priority.

Promising second-year lineman T.J. Lang might be the Packers' right tackle of the future — or a guard — but McCarthy acknowledged the team might have to put off Lang's long-term development to make him Plan B at left tackle.

"History will tell you that Chad Clifton is not going to play 16 games," McCarthy said recently. "You have to make sure the next guy is ready. That's where the challenge is. Do you line up and make sure T.J. gets all those reps or do you give him a chance to go compete for a job at right tackle?"

But if the Packers picked up a left tackle understudy with the No. 23 overall pick, McCarthy has more options.

The team went into last season hoping that Allen Barbre, a fourth-round pick in 2007, could take over at right tackle. But Barbre wasn't up to the task, Rodgers was being sacked at an alarming rate, and the team had to turn back to Tauscher, who was out of football after a season-ending knee injury in 2009.

The Packers also tried to grab a sleeper future starter, Jamon Meredith, in the fifth round last year. They tried to stash him on the practice squad, but he was signed away by the Buffalo Bills.

Still, Thompson says the Packers aren't under pressure to find a future left tackle in this draft.

"I think our core is building up to where we can have a little more flexibility," Thompson said. "But at the same time, it is what it is. If there's someone available we think can do that, certainly that's going to be a consideration. But we're not going to reach on something."

Green Bay's first-round options at tackle could include Rutgers' Anthony Davis or Maryland's Bruce Campbell.

Then there's cornerback, where Woodson was the 2009 Defensive Player of the Year and is showing no signs of slowing down at age 33. There are more questions about Harris, who is 35 and coming off that knee injury.

McCarthy said he "wouldn't bet against" Harris being ready for the start of the season, but also acknowledged Harris' injury was "significant."

Tramon Williams is a good No. 3 cornerback, but there isn't much depth behind him, a fact made painfully apparent at the end of last season, when the Packers' defense was shredded by multiple-receiver formations.

Two of the Packers' most promising options behind Williams, Will Blackmon and Pat Lee, both are coming off season-ending knee injuries as well.

First-round options at cornerback for the Packers could include Rutgers' Devin McCourty, Boise State's Kyle Wilson or Alabama's Kareem Jackson.

Then there's outside linebacker, where 2009 seventh-round pick Brad Jones did an admirable job filling in after a season-ending knee injury to Aaron Kampman. Now Kampman is gone through free agency, and Jones and Brady Poppinga could be options to start opposite Clay Matthews III. But the Packers could be tempted by Michigan's Brandon Graham or Texas' Sergio Kindle in the first round.

Another need that could be addressed in later rounds is at punter, an unsettled position in Green Bay for several seasons. After the Packers parted with Jeremy Kapinos, the only punters on the roster are former University of Kentucky kicker Tim Masthay and Chris Bryan, a former Australian rules football player.