"I don't know that I could give you an answer except that it ticks me off and we've been working on it," Williams said on Friday when asked about his perimeter defense in ACC play.
The statistical trend is clearly working in the wrong direction. North Carolina held its first four opponents – Gardner-Webb, Florida Atlantic, Long Beach State and Mississippi State – below their season averages from 3-point range. Since that time, however, nine of UNC's last 12 opponents have shot above the season averages from behind the arc against the Tar Heels. One of the three teams to shoot below its season average was Indiana, which shot 40 percent (8-of-20) against UNC, down from its 41.3 percent standard.
North Carolina's last 12 opponents have combined to shoot 39.6 percent from 3-point range.
Freshman point guard Marcus Paige offered his opinions on cutting that percentage on Friday.
"The biggest key for us to defending the 3-ball is guarding the ball better," Paige said. "When you allow a direct drive - we focus on a lot of support defense - so we have to have help and we like to get our help from our guards before our big guys have to help.
"So if we can stay in front of the ball better, then they won't get as good of shots. Coach has shown us that in film, times when we've really defended the ball well and they take a bad, contested three. And then they'll show us times when our defense breaks down and they have a wide open three. Just containing the ball better will probably lower that percentage a lot."
Paige's explanation details in part the emphasis of Williams's defensive philosophy – preventing the high percentage shot at the occasional expense of a 3-point attempt. As noted above, it's not as though this season is an anomaly, although UNC's 3-point field goal percentage defense numbers are higher than normal.
North Carolina's average ACC ranking during the first nine seasons of the Williams era was sixth defending the three. Only two of those nine teams held their opponents below 33 percent shooting. The 2011-12 squad's 31.9 percent effort in guarding the three – good for 64th nationally -- represented the top mark during Williams's tenure.
The Tar Heels, however, have ranked in the top half of the ACC in field goal percentage defense in all but two of the last nine years, which provides some context to why if UNC breaks down defensively, it's almost always from 20 feet out instead of under the basket.
Former UNC basketball manager and current InsideCarolina.com analyst Tyler Brooks says Williams is all about the high percentage shot, both on offense and defense.
If a UNC defender allows dribble penetration, the next closest Tar Heel is responsible for stepping over to stop the drive. If it's a guard helping, then his man may have an open look from behind the arc. If a post player helps, the closest guard is tasked with defending the passing lane to the now-open big man.
"In other words, if there is going to be someone open at any location on the floor, it better be behind the arc as opposed to right under the goal," Brooks said. "Obviously with optimal execution there should not be anyone open at all."
Brooks also dismisses the claim that Williams is incapable of coaching against the 3-ball.
"Williams would rather see his players help their teammates in a collective attempt to keep the ball out of the middle and away from the basket than to implement a strategy with no help defense on dribble penetration or off-ball movement, even if this strategy is the best way to prevent open three point attempts," Brooks said.
Remember all of those open looks that Virginia and Miami got from behind the arc? The help defense that UNC employed on those occasions was due more to a breakdown in execution rather than an indictment of UNC's preferred strategy.
It would appear North Carolina should get a reprieve over its next two games as Maryland and Georgia Tech rank 10th and 12th in 3-point field goal percentage in ACC games, respectively. History, however, may suggest otherwise.