North Carolina (28-4) only needed five minutes and 15 seconds to open up a 10-point lead on Maryland (17-15), but the Terrapins closed the gap to 22-19 with a 9-2 run. UNC held Maryland scoreless for the final 3:36 and took a 36-26 lead into halftime.
The Tar Heels scored eight straight points to build an 18-point lead just two minutes into the second half, but Maryland kept fighting and cut the deficit to 52-45 with a 14-4 spurt. UNC soon responded, however, with a 9-0 run and the Terrapins were unable to get within 12 points again.
Henson was fouled hard on a shot attempt early in the first half and went to the locker room at the 13:51 mark and did not return. X-rays were negative on his wrist.
Reggie Bullock and Harrison Barnes both scored 15 points to lead North Carolina. Kendall Marshall broke the ACC single-season assist record and finished with 13 points, 12 assists and six turnovers. Tyler Zeller added 14 points and seven rebounds, while James Michael McAdoo posted 14 points and eight rebounds.
Terrell Stoglin paced Maryland with 30 points on 11-of-21 shooting, including a 5-of-11 effort from 3-point territory. Nick Faust (11) and Sean Mosley (10) also scored in double figures for the Terrapins.
North Carolina shot 50.8 percent (31-of-61) from the floor, while holding Maryland to 38.7 percent (24-of-62). UNC won the rebounding battle, 41-34.
UNC will play No. 5 seed N.C. State in semifinal action on Saturday.
INSIDE THE GAME
Marshall Breaks ACC Assist Record
Ten days ago, Marshall only needed four assists to break Ed Cota's school record for single-season assists, but it took 22:01 of game time for the sophomore point guard to reach that mark.
Marshall needed five assists on Friday to surpass Georgia Tech's Craig Neal (303) for the ACC single-season record, but there was no delay this time. Marshall assisted on UNC's first five field goals and set a new record on a pass to Barnes – who also scored the basket to break the school mark – just 4:29 into the quarterfinal contest.
UNC head coach Roy Williams opened his postgame press conference by congratulating his point guard.
"We've been playing basketball [in the ACC] for a long time and there's been a lot of great point guards," Williams said. "Kendall Marshall's had more assists in any season than anyone else, so that's fantastic."
Marshall has been tracking this record all season long, but now that he's set a new record, he has a new goal in mind.
"I just want to make sure it's not broken," Marshall said. "I hear players talk all of the time when their records are broken about how proud they are. Honestly, I think I'm going to be a little mad if somebody ever breaks mine."
Marshall now has 311 assists on the season and delivered his 14th double-digit assist game of the year on Friday. Up next is former N.C. State point guard Chris Corchiani's ACC record of 15 double-digit assist games in 1990-91.
If Henson's injury wasn't bad enough, Zeller found himself in foul trouble, eventually picking up his fourth foul with 9:57 to play.
Enter freshmen James Michael McAdoo, Desmond Hubert, P.J. Hairston, Stilman White and senior Justin Watts.
McAdoo matched his season high in points and led UNC with eight rebounds in 29 minutes. Hairston scored nine points on 3-of-6 shooting, which represents his highest output since scoring 16 against Monmouth in Jan. 1.
"James Michael was big for us today; P.J. was big," Williams said. "That last three that P.J. shot that went in and out and came back in and went back out, that's just the story of his season so far."
White's eight minutes helped hold Marshall's total to 32 minutes, and Hubert logged six minutes in post relief.
With 4:21 to play in the first half, the four freshmen joined Barnes for a brief stint after Marshall picked up his second foul. Maryland failed to take advantage and was unable to cut into UNC's lead.
For a team short on depth, Friday's experience for the reserves can only pay dividends as the Tar Heels progress into March Madness.
"I think this might have been the biggest game of the year for our bench," Marshall said. "I think they gained a lot of confidence out of that, because they're players that are going to have to help us down the stretch. I think they showed today that they can do that."
Trouble Below for the Terps
How's this for a telling observation: Maryland's frontcourt did not score a point until forward Ashton Pankey made a basket with 12:19 to play in the game.
Stoglin, Faust and Mosley combined for the Terrapins' first 43 points and 51 of their 69 overall.
Despite the ACC Defensive Player of the Year only logging seven minutes of action, Maryland's starting frontcourt – Alex Len and James Padgett – was held scoreless on a combined 0-of-7 shooting effort. That duo also managed just four rebounds, prompting Maryland head coach Mark Turgeon to play Pankey (7 points, 8 rebs) for 30 minutes.
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