Arizona was no longer just a nice little regional story from an afterthought of a conference.
Not after the second-half smackdown the fifth-seeded Wildcats administered Thursday night at Honda Center during a 93-77 drubbing of top-seeded Duke in an NCAA West Regional semifinal.
Arizona outscored the defending national champions by 22 points over the final 20 minutes, getting contributions from almost its entire roster following a first-half breakthrough by Williams in which the sophomore forward scored 25 of his career-high 32 points.
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"Anyone who scores 25 points in one half on Duke," Wildcats guard Kevin Parrom said, "his name is Superman."
The hero had plenty of sidekicks during Arizona's game-turning 19-2 surge early in the second half that transformed a six-point deficit into an 11-point cushion. Williams scored only two points during the run that started with forward Jesse Perry's jumper with 16 minutes 19 seconds left.
There was also a three-pointer from forward Jamelle Horne, a driving layup from Parrom and a steal and dunk from seldom-used guard Brendon Lavender.
"That just shows the depth on our team," Arizona guard Jordin Mayes said, "that it's not a one-man show."
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Guard Lamont Jones scored 16 points and forward Solomon Hill had 13 for Arizona (30-7), which will play third-seeded Connecticut (29-9) on Saturday in its first regional final since 2005.
The Wildcats' victory was a major triumph for the Pacific 10 Conference, which has not advanced a team this deep into the NCAA tournament since UCLA made the Final Four in 2008.
"The Elite Eight is great, but we're not looking to stop right there," said Williams, who made 11 of 17 shots, including five of six three-pointers. "We're trying to win a national championship one step at a time, and one more game we're in the Final Four."
After trailing by six points at halftime, Arizona manhandled Duke (32-5) in almost every facet in the second half.
The Wildcats had a 25-9 edge in rebounding and a 24-6 advantage in points in the paint while shooting 58.3% to Duke's 37.5%
There was still 6:47 remaining when Horne started exchanging celebratory hugs with teammates during a timeout huddle after dunking over Duke's Kyle Singler to give the Wildcats a 77-63 advantage.
With his team headed to its most lopsided defeat of the season, Duke Coach Mike Krzyzewski pulled Singler and fellow senior Nolan Smith from the game with 2:01 left.
Krzyzewski finished the season two victories short of tying former mentor Bob Knight's record of 902 Division I coaching victories. The Blue Devils entered the game with the highest winning percentage in NCAA tournament history but are now 0-2 at Honda Center after also dropping a regional semifinal here in 2003 against Kansas.
Duke's Kyrie Irving had 28 points off the bench, but the vaunted Blue Devils guards couldn't outclass their Arizona counterparts as expected.
Williams had 25 points by halftime, punctuating a dizzying display of put-backs and three-pointers with a shot from about 30 feet over the outstretched arms of 6-foot-11 forward Ryan Kelly one second before the buzzer.
"That one at the end of the half, that kind of sums it all up," Duke forward Mason Plumlee said. "He was on fire."