There are bad defensive backfields, and then there's Purdue.

If the Boilermaker secondary was to be given a theme song this season, Tom Petty's "Into the Great Wide Open" might be the most appropriate choice.

Purdue's pass defense ranks 108th out of 119 teams in the country, surrendering 249 yards per game while allowing 66 percent of passes to be completed.

The defense as a whole is No. 111 in the nation.

The Boilermakers yield 7.9 yards per passing attempt -- meaning that, on average, if an offense throws the ball on first down against Purdue, the next play will be second-and-2. Second-and-short, by the way, affords an offense optimal freedom in its playcalling, something that may benefit Penn State.

The starting secondary for Purdue consists of a pair of true freshmen and two junior college transfers in their first autumn at West Lafayette.

"When we started the season, we didn't have a single starter in our secondary that was with us last spring," Purdue coach Joe Tiller said. "So it was a totally new collection of talent, and that takes time to get used to one another and gain experience that is so valuable in the secondary."

While the Boilermakers continue to get used to one another and gain experience, Penn State's receivers look to get used to the feeling of scoring touchdowns, a feeling they have not experienced in some time.

Penn State's top three receivers -- Derrick Williams, Deon Butler and Jordan Norwood -- have not scored a touchdown since the second week of the season at Notre Dame, some seven weeks ago.

"We really thought that we'd light up the numbers this year, especially with the receivers that we had," Williams said.

The Nittany Lions typically neglect the middle of the field, figuring their pass protection is too inept to stave off the oncoming rushers, leaving Anthony Morelli little time to locate receivers on slow-developing routes between the hashes.

"It takes a while to get some guys in there over the middle...We are not throwing the ball as much over the middle as we would like to do it, but that takes a little time to get that thing developed," Joe Paterno said. "A couple of times we tried, but we just have to start with pass protection and have to do a better job."

Though Purdue defensive end Anthony Spencer will make pass protection a challenge, the option of calling draws and screens should be available to the Lions if they wish to exploit any defensive aggressiveness.

Tony Hunt was stymied by poor blocking in front of him the past two weeks, but should Penn State establish the threat of the downfield pass, running lanes might open up for the senior tailback.