Coming off a national championship and a roster overhaul, coaches picked North Carolina No. 4 in the nation in the preseason coaches’ poll released Thursday.

Duke, who reached the Sweet 16 before losing by 23 points to eventual Final Four-bound Villanova, is ranked No. 8 in the poll.

Both teams tied for first in the ACC preseason poll — the first time in ACC history the league has had co-favorites; both teams have top-10 recruiting classes (No. 3 for UNC, No. 8 for Duke according to; both teams made the top 10 in the preseason poll for the second season in a row.

Most importantly, both teams have big question marks heading into the season. Duke lost its offensive catalysts when Gerald Henderson (NBA draft) and Elliot Williams (transferred to Memphis) left the team. The Blue Devils are still searching for a difference maker at point guard until 2010 stud Kyrie Irving can come to town, and post production is still unproven with a lot of youth.

But the Blue Devils do return Mr. Everything, Kyle Singler, who will play on the wing this season due to greater depth in the frontcourt and a lack of depth in the backcourt.

The Tar Heels have more questions than answers and should not be ranked as high as they are yet alone ahead of Duke. UNC lost some guy named Tyler Hansbrough, who produced point after point in the paint for four years. Deon Thompson and Ed Davis won’t be able to completely fill Hansbrough’s offensive void. Not to mention the lack of a 3-point shooting threat with Marcus Ginyard being the only formidable shooter returning other than unproven freshman Leslie McDonald and Dexter Strickland.

Most analysts peg the Tar Heels’ hope of repeating on sophomore point guard Larry Drew II, but the overall point production from the backcourt will be an adventure throughout the season. Ginyard and Drew are not known for their scoring. Both worked on their shots this offseason, and UNC will need them to step up, especially come conference play.

UNC will be battle tested by the time ACC conference play begins. The Heels face three teams in the preseason top five (No. 2 Michigan State, No. 3 Texas and No. 5 Kentucky). It should be interesting how the pollsters and the selection committee treat the immature Heels if they lose several of these games close.