INDIANAPOLIS (AP) -- Bill Polian knew Peyton Manning needed a bodyguard.
Anthony Castonzo was willing to take the job.
Now, the tandem could be working together for the rest of Manning's NFL career. The Colts selected the 6-foot-7, 311-pound Boston College alum with the 22nd overall pick, making Castonzo the new heir apparent at left tackle.
"You've got to be excited about it," Castonzo said, moments after he jumped in the air with his family in Illinois. "I get to play with one of the best quarterbacks in the league. You couldn't ask for any more than that."
Actually, that's only part of the job, rookie.
Castonzo is expected to protect the blind side for the league's most durable quarterback and a four-time MVP that the Colts cannot afford to lose to injury. Team officials believe Castonzo can solidify an offensive line that has spent most of the past two seasons playing musical chairs.
Now Castonzo, a biochemistry major, will now go under the microscope himself.
"I'm going to have learn a lot for sure," the former Rhodes Scholar candidate said.
He also has a lot to live up to after becoming the first offensive lineman chosen in the first round of the Manning era. The last time Indy took a tackle this high was 1997 when Tarik Glenn went 19th overall.
Glenn became Manning's personal protector for the first nine seasons of Manning's career, but his abrupt retirement following the 2006 season left a hole that the Colts never really filled.
They thought 2007 second-round pick Tony Ugoh would emerge as their left tackle of the future. Instead the Colts released Ugoh last summer after four mostly sub-par seasons.
Ugoh lost his starting job in 2009 to Charlie Johnson, who had spent most of his first three NFL seasons playing guard. The switch, and a rash of injuries, forced the Colts to continually plug holes by moving guys around.
Now with Castonzo taking over the blind side, all that might finally end.
"It gives us a player we can plug in at one position, and it stops some of the musical chairs we've had to deal with the last couple of years," general manager Chris Polian said.
Over the last two seasons, Manning was hit more frequently than the Colts' wanted, and Indy has not had a 1,000-yard runner since 2008.
Things got so bad that team president Bill Polian publicly blamed the offensive line for the Super Bowl loss to New Orleans because of the Colts' inability to convert short-yardage plays.
They're hoping Castonzo is part of the solution. He's bigger than a typical Colts' linemen, known as a good pass protector and a solid run blocker who made 54 consecutive starts at Boston College. There, he manned the left side for future first-round pick Matt Ryan.
But the biggest surprise for the Colts was that he was still available at No. 22.
"He's pretty much everything we look for in a player, and I'm sure he can come in and do a good job soon," said Bill Polian, now the Colts' vice chairman. "Believe it or not, we spent the last four days going through scenarios and his name was never mentioned. But the quarterbacks changed all that."
Indy may not be finished overhauling the line, either.
The lifting of the lockout could give Indy a chance to start signing free agents -- its own and those from other teams -- early next week.
Plus, the Colts still have five more draft picks to use over the next two days.
"It's possible," team owner Jim Irsay said when asked if they would take another offensive lineman. "We could add two guys at this point with the changing aspect of our team with age and stuff. But I think we do have some other needs, too."
Castonzo just filled one hole, prompting him to gladly to put his other career on hold to block for Manning.
"I probably would have gone to medical school and gone into medical research or something like that," Castonzo said, laughing. "My family, they're pretty much as excited as you could possibly be and absolutely ecstatic. It's a dream come true, really."