CBSSports.com reports that Marshall will undergo surgery on Monday morning to insert a screw in the injured wrist. A determination on whether or not he'll be able to play will be made at a later date.
"All we know is that it's a fracture," a teary-eyed Marshall told reporters following the game. "I get on the bus. That's the next step."
Marshall, who naturally shoots left-handed, fell to the ground after being fouled by Creighton's Ethan Wragge at 10:56 in the second half, and used his right hand to brace his fall.
The sophomore point guard shot two free throws after a media timeout, making the first. He subbed out at 10:24, but returned at the 8:52 mark. Marshall missed another free throw with 7:09 remaining, but did not attempt another shot before exiting the game for good with 1:54 to play.
"When I first fell, it was more of my funny bone that hurt," Marshall said. "But it started hurting a little bit more as the game wore on."
When asked when he felt the most pain, Marshall replied: "Any time I tried to dribble with my right hand."
Marshall's wrist was wrapped with ice during his postgame interview, but indicated that it had already started to swell "a little bit."
The Cousy Award frontrunner took the news hard when he learned the severity of his injury after the game.
"It hurt… it hurt," Marshall said. "First and foremost, I hurt for my team because I want to be there and be able to help them to the best of my ability. So once they told me, I took it a little hard. I told my parents and we took it a little hard."
An emotional Roy Williams said postgame that no further information was available, and UNC said Marshall's status is "unknown" for its Sweet 16 game.
Williams did say that Stilman White or Justin Watts would be the likely point guard options if Marshall is unable to play on Friday.
"When you go to the Sweet 16, it's supposed to be a lot more fun than this," Williams said.
Marshall posted a team-high 18 points and 11 assists in the win.