That moment when Harrison Barnes went to Skype to tell Roy Williams he was coming to Chapel Hill loomed large on Saturday, when North Carolina captured a stunning ACC title with 81-67 victory over Duke.

This season swung on two critical points. The first, of course, was Barnes’ remarkable decision to attend UNC after many insiders thought he would head to Durham. The second, of course, was the toe injury to Duke freshman Kyrie Irving.

But who could have thought Barnes would draw the assignment of covering Kyle Singler – a preseason national player of the year candidate  – and outplay Singler so decisively?

Singler’s perplexing slump continued with a three of 14 shooting effort and only eight points. Duke coach Mike Krzyzewski has touted Singler as one of Duke’s best defensive players in his tenure, perhaps a way to keep Singler’s confidence high, but Barnes got off good shots against him and hit 7 of 17 from the field for 18 points.

Barnes hit big shots and gained confidence as the game continued. Duke never got on a roll late, and Nolan Smith and Seth Curry couldn’t find a third scorer to get the offense untracked.

You would think that Singler would be that guy, but the touch again was missing. Part of that was certainly Barnes, whose decision to attend Carolina had an enormous impact on Saturday’s game. Think of it like this – can you imagine how great Duke would be with a healthy Irving and Barnes in the lineup?