Zeller got caught on a switch defending Rivers on the final possession and said he should've played him closer.
"I knew he was going to shoot a 3," Barnes said. "I thought everyone in the gym knew. Z did a good job of contesting, but he made the shot."
Then again, North Carolina probably never should've let it come to that.
After trailing most of the first half, the Tar Heels ran off a 14-4 run to start the second half. Barnes didn't have a field goal in the first half while playing on his sore left ankle, but he finally got going with a pair of baskets followed by a 3-pointer off a crosscourt pass from Kendall Marshall for a 57-44 lead with 15:08 left.
North Carolina maintained at least a seven-point lead until those final minutes, with Barnes' last jumper giving the Tar Heels an 82-72 lead with 2:38 left.
North Carolina shot 59 percent in the second half, but went just 8 for 15 from the foul line after halftime to let this one slip painfully away.
"This one hurts," UNC coach Roy Williams said. "The kids really played and competed and did some very good things."
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