"I really appreciated the second half a lot more than the first because of our energy," Duke coach Joanne P. McCallie said. "I love our 28 offensive rebounds.
"I thought Elizabeth made the most of her time out there, looking to attack, and I thought Sierra was great leading by example."
Camera Miley led Buffalo (2-2) with a career-high 15 points, and Alexus Malone had 14 in the teams' first meeting.
Buffalo coach Felicia Legette-Jack was an assistant to McCallie at Michigan State when the Spartans lost the 2005 NCAA championship game to Baylor.
"What a sensational team you get to witness on a daily basis," Legette-Jack said. "That's the best team I've ever coached against, and I've played at Indiana and Notre Dame and Kentucky and West Virginia. This (Duke) team is really a special team.
"But I'll take my hat off to my kids for doing a great job in the first half, in the moment understanding that each possession mattered."
Duke shot 44 percent and had a school-record 69 rebounds. Buffalo shot 25 percent from the field and had 31 boards.
Williams had 12 points in the first half to lead the Blue Devils to a 36-25 lead at the break.
"(The freshmen) have done a great job," Williams said. "I think I have said it before, but I have the utmost faith in our team. They showed it today with four of the freshmen in double figures and Sierra was great on the line and getting rebounds. Obviously I have a job to do, but a lot of that is pushing my teammates to do what they're capable of doing."
TIP-INS Duke: It was the Blue Devils' 134th straight victory over an unranked non-conference opponent at Cameron Indoor Stadium. ... Williams, who played only 22 minutes, has scored in double figures in 12 straight games.
Buffalo: Leggette-Jack said the massive snowstorm in the Buffalo area had dropped only eight inches on campus, less than a tenth of what fell around parts of the metro area. "Our family and friends and assistant coaches were stuck in their homes and could not ever open their doors," she said.