"It was strange because in 2012 we had lost John Henson during the ACC Tournament and then we got him back, but he wasn't full speed," Williams said Saturday. "They say you cut off the head of the snake, you really bother him, and that's what happened when we lost Kendall."
Niang may not quite be the head of the snake for Iowa State, but he's been the most important player for the Cyclones recently. He's averaged a team-high 20.4 points in the last five games.
The loss drastically alters Iowa State's lineup — Niang was the tallest player of a seven-man rotation used by coach Fred Hoiberg.
Friday night, Niang hit four of five 3-pointers and scored a game-high 24 points before getting injured with fewer than eight minutes left in the game.
Though the Tar Heels can empathize with the Cyclones and relate to the sadness that comes with the loss of a star player, UNC is wary of the motivation Iowa State will carry into Sunday night's game.
"Coach (Dean) Smith used to say he hated to play somebody when they just lost one of their frontline players because everybody banded together even more and were more motivated and all that kind of thing," Williams said.
The loss of Niang also puts a giant question mark in the Cyclones' starting lineup. Saturday afternoon, Hoiberg still hadn't decided who would take Niang's spot in the starting five — something that Williams said gives Iowa State a bit of an edge.
"I wouldn't be surprised if Fred (Hoiberg) would say there is some indecision about what they're going to do and that kind of thing," Williams said. "But it's easier on their side because they control it, and we're reacting to what they do.
"But it is a big?time loss for them. But they can spread you even more now, and that's something that's difficult for us because we like to play some big guys."
When Williams was faced with a similar conflict in 2012, he turned to a 5-foot-10 reserve point guard.
Stilman White had played only garbage minutes for the Tar Heels up to that point, and suddenly he was the new floor general, replacing eventual Cousy Award winner Marshall.
But in his two games as a starter, White dished out 13 assists and scored six points. He couldn't fill Marshall's shoes, but he gave the Tar Heels a fighting chance before losing to Kansas in the Elite Eight.
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"It was a great opportunity for guys to step up like myself as well as Stilman, Justin Watts," James Michael McAdoo said. "I think it just came down to at the end of the day, we had guys who were capable of winning the ball games."
Iowa State is certainly capable of also fielding a team capable of winning games. The Cyclones still have All American and Big 12 Player of the Year Melvin Ejim and the Big 12 Championship Most Outstanding Player DeAndre Kane at their disposal.
The loss of one player doesn't automatically swing momentum in the Tar Heels' favor.
They know that. They've been here before. And Sunday night, it will be up to UNC to react quickly to whatever the Cyclones throw at them, with or without Niang.