CHAPEL HILL, N.C. -- With 1:38 left in last Sunday night’s first half, John Henson went airborne in the lane to swat away Georgia Tech guard Jason Morris' shot.

It was a move fans had seen before from the North Carolina forward -- 245 times previously in a Tar Heel uniform, in fact, in different variations. And because of all the activity since -- another victory Tuesday at Wake Forest, teammate Harrison Barnes’ sprained ankle, and preparations for Saturday’s game at Maryland -- that particular block might have long been forgotten.

That is, if it didn’t have so much significance.

The rejection pushed Henson to second on UNC’s all-time blocks list, passing Sam Perkins, who swatted 245 from 1980-84. After blocking a total of four shots against the Yellow Jackets, and four more at the Demon Deacons, Henson now stands at 251 for his career -- 53 away from Brendan Haywood, who leads the school record books with 304.

“It’s a big compliment -- any time I can squeeze my name between Brendan Haywood and Sam Perkins, it’s always good,’’ Henson said. “It’s a special thing, and I’m glad I had the opportunity to do it.”

The impressive thing is how fast the junior has managed to catch up to the four-year players – and how much faster he might have been able to do so if he had played in the post from the beginning.

Remember: the 6-foot-11 Henson started his career playing small forward for the Tar Heels, struggling so much in that position that he often played only single-digit minutes.

It was only after forward Ed Davis broke a bone in his wrist that Henson moved to the post and thrived. Among other things, he began his swat-fest, recording 30 of his 60 blocks that year in the final 13 games of that 2009-10 season.

“It is impressive,” Coach Roy Williams said of Henson’s blocks tally, “especially considering his freshman year, he spent so much time out away from the basket, trying to guard people on the perimeter until we had those injuries. He’s been really dominating defensively -- and not just with the blocked shots, but sliding his feet and cutting off the passing lanes and helping the guards.”

Williams has called Henson (last season's ACC Defensive Player of the Year) one of the best shot blockers he has ever coached. And that includes Perkins, who Williams helped recruit when he was an assistant under Dean Smith.

“We felt that Sam could guard anybody,’’ Williams said. “He could slide his feet as well as anybody, and John’s coming close to that. … Sam was a little bigger, a little stronger inside, too. But John’s probably a better shot blocker than Sam was, and I think he’s showing that right now.”

The question is, how quickly can Henson catch Haywood, who he practiced against during pick-up games this summer?

If UNC advances to both the ACC tournament title game and the NCAA championship game, the sixth-ranked Tar Heels will have a maximum of 18 more match-ups this season. That means Henson would need to average 2.94 blocks the rest of the way to catch Haywood without returning for his senior season. Considering he’s averaged a league-leading 3.3 so far, the possibility is not much of a reach.

And he is used to stretching, especially when it comes to blocks.

“He’s extremely long, and he’s the only person I’ve ever seen that can consistently get to my hook shot – it’s pretty tough to block, but he can get up there and change it and challenge it,’’ 7-foot teammate Tyler Zeller said. “I have so much confidence in him in the post, that when he goes up and misses it, I’m sometimes surprised.”