Four months ago, Duke appeared in danger of falling alarmingly far behind North Carolina in the basketball rivalry that never fails to capture the nation's attention.
Under coach Roy Williams, the Tar Heels had been to three Final Fours and won two NCAA titles since the last time Duke went to the Final Four in 2004.
North Carolina had won six of the last seven in a series that coach Mike Krzyzewski and Duke had dominated for six years.
And on Nov. 13, forward Harrison Barnes of Ames High in Iowa signed with North Carolina, giving Williams the nation's top-rated recruit in the Class of 2010. Duke also was one of the finalists for Barnes, and losing him to North Carolina seemed to be a catastrophic blow in the rivalry.
But North Carolina unexpectedly is a lower-division ACC team instead of a conference title contender this season. And it appears that the Tar Heels might need Barnes just to keep up with a resurgent Duke team.
"Not getting Harrison Barnes was not the demise or imbalance of the rivalry between Duke and North Carolina," All-Star Sports recruiting analyst Bob Gibbons said. "North Carolina is fortunate that they got Harrison Barnes because it brings it up to where they will be more competitive with Duke and other teams next year."
Fourth-ranked Duke (25-5, 12-3 ACC) has lived up to preseason expectations as it prepares to play host to North Carolina (16-14, 5-10) in the regular-season finale at 9 p.m. today.
Duke can claim at least a share of the ACC regular-season title and capture the No. 1 seed for next week's ACC Tournament if it can complete the season sweep with a win tonight.
Now it's the Tar Heels who look like they need to keep up with Duke.
Krzyzewski's 30th Duke team is bigger than any other he's coached.
The Blue Devils have used their size to lead the ACC in rebound margin (plus-6.0 per game). While the big guys have crashed the boards, forward Kyle Singler (17.0 ppg) and guards Jon Scheyer (18.8 ppg) and Nolan Smith (17.5 ppg) have accounted for 66 percent of the points as the second-highest scoring trio in the nation.
That formula has Duke tied with Maryland atop the ACC standings and poised for a No. 2 or perhaps a No. 1 regional seed in the NCAA Tournament.
The Blue Devils have continued their incremental climb toward national elite status after posting a disappointing 22-11 record and losing in the first round of the 2007 NCAA Tournament when the current seniors were freshmen.
Duke seems likely to remain near the top of the ACC. Mason and Miles Plumlee are promising post players, and Smith will return as a backcourt leader next season.
Singler's decision on whether to return for his senior season will determine whether Duke is slotted in the preseason top five or top 15 nationally. Krzyzewski has said Singler will wait until after the season to decide.
Duke's backcourt should remain strong, with highly regarded freshman point guard Kyrie Irving and transfer Seth Curry joining Smith.
Teammates say former Liberty guard Curry - the brother of Golden State Warriors guard Stephen Curry - has demonstrated in practice that he's a superb shooter.