Thomas scored 24 points to set the program record midway through the second half of Friday's 73-70 loss to No. 13 North Carolina in the quarterfinals. The 6-foot-2 senior is now 12 away from passing Juan Dixon for the most points by a men's or women's player heading into her final NCAA tournament.
She just couldn't quite lead the Terrapins' second-half comeback, missing two shots and committing a turnover in the final 90 seconds of a tight game.
Afterward, the three-time ACC player of the year said it was an honor but also "something I'm not really thinking about."
Her coach, Brenda Frese, was in a better position to appreciate the significance of Thomas passing Crystal Langhorne, who was on Frese's 2006 NCAA championship team.
"I know she's not going to appreciate it right now because of the competitor and winner that she is," Frese said. "She would turn all of that away to get that win. But yeah, absolutely. I mean, (after) everything that she's meant to our program, to our university, and it's only fitting for her to be the all-time leading scorer at Maryland."
For North Carolina, Diamond DeShields scored 22 points while fellow freshman Allisha Gray added 17.
Xylina McDaniel added 10 points for the sixth-seeded Tar Heels (24-8), who led all but 5 seconds but still had to fight to put away the Big Ten-bound Terrapins (24-6) in what turned out to be their final ACC game.
UNC advanced to Saturday's semifinals to play No. 10 Duke.
The Tar Heels led by 11 at halftime but missed their final 10 shots and went the final 5:27 without a field goal. Still, they did just enough to hang on and earn a shot at a three-game sweep of the rival Blue Devils this season.
Maryland closed UNC's lead with back-to-back of baskets from Lexie Brown before Thomas hit a pullup jumper to make it 71-70 with 1:35 left.
But going 1-on-1 against McDaniel in the final minute, she bobbled the dribble near the foul line and lost the ball, with a tie-up during a scramble giving the jump ball to North Carolina with 17.8 seconds left.
Brittany Rountree hit two free throws with 16 seconds left to push the margin back to three, then Thomas missed a straightaway 3 for the tie in the final seconds. Brionna Jones got the rebound and was fouled with 2.5 seconds left, but she missed the first free throw to set up an intentional miss on the second that UNC's Danielle Butts rebounded to seal the win.
Maryland fans knew this would be their last trip to the Greensboro Coliseum before the school's Big Ten departure in July. Before the game, several Terrapins fans held up a sign that read "Thank you Greensboro," where they won the 2009 and 2012 ACC tournament titles under Frese.
It turned out their final stay here ended up being much shorter than they expected thanks largely to the Tar Heels' talented freshman duo.
DeShields went 9 for 20 and hit two 3-pointers in 37 minutes.
Gray didn't play in the second half of Thursday's second-round win against Wake Forest after she hit her head on the court while being fouled shortly before halftime. She started Friday night and missed her first four shots before finishing 6 for 12 with two 3-pointers.
Thomas hit a pullup jumper at the 11:19 mark to break Langhorne's program record of 2,247 career points.
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