It's out there, lurking, waiting for them at nearly every turn of the ACC schedule.
Although it won't always pop up, it certainly has caused its share of problems.
The zone defense, particularly of the 2-3 persuasion, is seemingly always prepped to hassle members of the North Carolina men's basketball team.
Why should tonight be any different?
Clemson enters tonight's 7 p.m. game at the Smith Center with a huge front line and a gaudy record (10-1, 0-1 in the ACC).
The Tigers have never beaten the Tar Heels in Chapel Hill -- they're 0-48 at the Old Tin Can, Woollen Gym, Carmichael Auditorium and the Smith Center -- but as always will look to abuse UNC inside.
And without the quickness to deal with the likes of Raymond Felton
UNC has seen the ol' 2-3 many times this season, with varying success, and at Virginia on Saturday, the Tar Heels looked like two different offensive teams before and after halftime.
In the first half, UNC dribbled and passed around the zone and was unable to get anything accomplished.