GREEN BAY, Wis. (AP) — The Green Bay Packers picked Iowa lineman Bryan Bulaga with the No. 23 overall pick in the NFL draft Thursday night, landing the left tackle they hope will protect their quarterbacks for years to come.

Bulaga, a 6-foot-5, 312-pound junior, immediately becomes the likely successor to veteran left tackle Chad Clifton. He also adds depth to what was one of the league's shakiest pass protection units last season as quarterback Aaron Rodgers was sacked 41 times in the first nine games alone.

Packers general manager Ted Thompson said he was "a little surprised" that Bulaga still was on the board.

"He's a finisher," Thompson said. "He's a tough guy, he's athletic, he's got great size."

Bulaga might begin his NFL career behind Clifton on the depth chart, but doesn't intend to stay there.

"I don't exactly know what my role will be, but I'm definitely going to come in and expect, push myself, to win a starting job," Bulaga said. "Obviously that's going to be my expectation. I'm still going to put that expectation on myself. I'm not going in thinking, 'Hey, I don't have to play right away.'"

Bulaga played left guard as a freshman, then moved to left tackle as a sophomore. Despite missing three games last season because of a viral infection in his thyroid, Bulaga passed up his senior year to enter the draft.

Bulaga said he has received regular checkups and hasn't had any problems with the illness since then.

"That was kind of a freak thing," Bulaga said.

Bulaga struggled in games against two of the Big Ten's best pass rushers last season, Michigan's Brandon Graham and Wisconsin's O'Brien Schofield.

He said he hadn't fully recovered from his illness in those games and would like another shot at blocking both players. He could see Graham right away; Graham was taken by Philadelphia at No. 13 overall and the Packers play the Eagles in their season opener.

Offensive tackle was the biggest position of need for the Packers, who also could use help at cornerback and outside linebacker. Thompson, however, insisted the pick wasn't made based on need.

"This was a value pick for us," Thompson said.

The Packers came into this year's draft needing help for an offensive line that allowed a league-worst 51 sacks last season.

Clifton and right tackle Mark Tauscher — who rejoined the team in the middle of last season to help stabilize the line's shaky pass protection — both re-signed with the Packers as unrestricted free agents earlier in the offseason. But both are in their 30s.

The Packers have a potential successor to Tauscher in second-year player T.J. Lang, although coach Mike McCarthy has said Lang's ideal position might be guard. The Packers didn't, however, have an obvious successor to Clifton.

And given Clifton's age and nagging injuries, establishing a backup plan was one of the Packers' top priorities.

Having taken care of that, the Packers could turn to other positions of need starting Friday.

There's cornerback, where Charles 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 fellow veteran Al Harris, who is 35 and coming off a season-ending knee injury.

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.

Green Bay also could use help at 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 has signed with Jacksonville, and Jones and Brady Poppinga could be options to start opposite Clay Matthews III.

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.