On the Knucklehead board some are concerned, some cautiously-optimistic, but many are flat-out wearing gold-shaded Ray-Bans...and good for them, I guess. At the very minimum, they'll enjoy their summer in bliss as they look ahead to the weather cooling down in God's country.

Regardless of where you stand in your prognostications, if you watched Purdue, you probably saw what we saw- there are a ton of question marks coming into this season. In our last segment of this three part series, we talked about the positives. In this part, we'll look at the things that concern us...if you don't like this part of the series, you'll hate part three.

But first, here we go:

-As confident as we are in the defensive backfield, we might be equally-doubt-filled about the

receiving corps...and that's not because there's not talent in the stable, but there's just so little that's been proven by this group...and that's a tough pill to swallow for a fanbase of the program that's produced some of the best college quarterbacks ever to play the game. Those great quarterbacks always had receivers and tight ends they could count on in the clutch- Smith, Bryant, Keller, Stubblefield, Davis, Standeford, Stratton, Sutherland, Daniels, Alford...all put up big numbers and were big-time threats. Amazingly, these guys all donned Purdue unis in just the last 15 years. But for the first time in a long time, Purdue returns no proven commodity in the hands positions.

The closest to proven is Antavian Edison...and the elusive, versatile receiver out of Fort Myers, FL has only had 330 yards receiving and 5 TDs in his career. After Edison, pretty much everyone is just great potential- The speedy OJ Ross could be a tough match-up, Justin Siller is as big and strong as about any receiver in the league and runs tight routs and Gary Bush could develop into a deep threat...but after that, the experience just isn't there.

Holmes or Sinz could become valuable dump-off options, Mostert might make a splash on his first year on campus, Harris could cross over to the offensive side of the ball and make noise, Macarthy might eventually follow in Smith and Siller's footsteps to become a big, capable receiver who was once a QB...Who knows. But, based on numbers and experience alone, there's not too much that's predictable in this corps and there's simply no known commodity.

-The penciled-in starting QB proved himself to be an elusive runner and inconsistent passer in '10. He only completed 53% of his passes, and had 8 TDs and 7 Ints last season after being rushed into the starting role following Marve's injury. At the same time, he led the team in rushing, averaging 5.3/attempt and a total of 547 yds and 4 rushing TDs.

You might think the latter part of those stats would make us happy, but a quarterback that struggles passing the ball and is successful rushing the ball only makes me more concerned as Purdue really needs to be able to pass with some consistency in '11.

Probably the most-concerning player in the stable is Marve- not because what he will or won't do on the field, but because I think every Purdue fan just wants to see him end his college career healthy. The last update we heard from Hope was that he's still still not 100%...and based on what we saw last season, Hope and Co. need everyone healthy...at least in the top-3 of the depth chart.

The last QB in that 3-man chart is TerBush whose potential is still pretty great, but outside of spot duty and spring scrimmages, no one really knows how he is in game situations.

-If Ralph Bolden had never gotten re-injured, and ATM hadn't transferred, I might not have RBs as a reason for concern...but both things happened, and Purdue's offensive backfield is once-again wrought with question marks.

Bolden says he's feeling great, but full contact is much different from limited contact, drills and workouts...but everyone's rooting for him to do big things. Behind Bolden, JuCo transfer, Shavers will most-definitely see action. After the top of the depth chart, the bigger backs; Pegram, Crank and Jackson might carry the ball a few times in short yardage situations. But I don't foresee a way that Edison and Ross will be able to avoid playing out of the backfield, at least every now and then.

-Defensively, Purdue loses the leading tackle-for-loss player for the past few seasons and a guaranteed double or triple with Ryan Kerrigan's departure. Maci, Mebane and the oft-injured speed rusher, Gooden will try to fill that vacuum on passing downs, and the under-experienced, but talented Frazier, Russell and even Kitchens will look to stop the run on the edges.

If Purdue had a monster opposite him and a young DE with a few starts under his belt to try to replace Kerrigan, we'd be concerned anyway...but a young guy who didn't play a ton and a guy who's struggled to reach his full potential makes us pretty nervous...even with the beef in the middle. This is kind of uncharted territory for us as fans, at least in the last 15-20 years as the Den of Defensive Ends has almost become an entity that doesn't rebuild, but reloads. I'm not too sure if I see an NFL-caliber DE in this corps...but there is potential in the group, just someone has to emerge in a hurry. The DBs should help those guys get up to speed.

-The schedule isn't the worst one we've ever seen...but there's plenty on the docket to make us take notice. First off, and perhaps surprisingly to some, Rice has ex-UM RB Sam McGuffie returning after leading them in rushing and receiving...plus they return most of the rest of their offense. If Purdue's defense can't stop the stuff underneath, one of the games that many thought would be an automatic win could end much differently. Notre Dame will be improved as they have experienced blue-chippers back on both sides of the ball and a coach that knows how to win. After UND, the B1G schedule is stout as usual...and I have a hard time finding four wins in the group...even with a couple of the powers suffering key losses at important positions.

Up next, we'll talk about the aspects of Purdue's 2011 team that have us nearly soiling ourselves.