Last season, the switch to a small lineup could only take the Tar Heels as far as the NCAA draw would allow. With Kansas's overwhelming size advantage in the post, UNC needed everything else to go right to pull off the upset, which never transpired.
With Marcus Paige representing UNC's lone perimeter threat this season due to the ongoing P.J. Hairston and Leslie McDonald eligibility fiasco, Williams is once again challenged by a flawed roster. While recruiting misses are a topic for another day, there is only so much a Hall of Fame coach can do midseason to develop a secondary perimeter scoring threat when there are no legitimate options on the bench.
For North Carolina to take up residence in the top-25 this season, the staples have to become the foundation. That includes energy level, rebounding, limiting turnovers and capitalizing at the free throw line.
Do those things – and add in a career performance by Paige – and UNC is capable of beating the top teams in the country. Just ask No. 7 Louisville.
Do anything less and losses to Belmont and UAB become realistic possibilities.
"Our margin is really small," Williams told reporters on Tuesday. "In '09, we could play really poorly and still win a lot of games. We could play without Ty Lawson, we could play without Tyler Hansbrough and some of those guys against pretty good teams and still win. We don't have that margin."
UNC lost at home to Belmont by three points and missed 26 free throws. The Tar Heels missed seven free throws (4-of-11) in their 63-59 loss at UAB on Sunday, but that statistic barely registered due to the Blazers dominating the glass.
Sophomore forward Brice Johnson pointed to the energy factor as being the primary difference between UNC's win over Louisville and its loss one week later to UAB.
"Everybody was a lot more energetic, talking a lot more on the defensive end; we were rebounding better," Johnson said. "Just energy. It didn't seem like we had any energy out there."
That lack of energy manifested itself on the backboards against the smaller Blazers.
"They outrebounded us 52-37 and they had 13 more possessions than we did," Williams said on his weekly radio show on Monday night. "We hold a team to 30.7 percent and we can't win the game because they have 13 more possessions. You can't beat people like that."
Especially when your team is limited offensively. UNC needs efficient scoring from the likes of Paige, James Michael McAdoo and Brice Johnson just to be competitive against elite-level teams like No. 1 Michigan State and No. 3 Kentucky over the next two weeks.
Without a sharp attentiveness toward the fundamentals, however, those offensive efforts likely won't be enough.
"We've got to play really, really well right now," Williams said.
That will be critical on Wednesday in East Lansing if UNC hopes to keep its roller coaster ride going with its second win over a top-five opponent in 10 days.