AUSTIN, Texas (Ticker) -- After using the 3-pointer to take the lead, Michigan State went to its top inside man to finish off Duke.
Alan Anderson hit three 3-pointers to spark an early second-half run and Paul Davis scored 10 points down the stretch as the sixth seed Spartans knocked off the top-seeded Blue Devils, 78-68, in the Austin Region semifinals.
Michigan State (25-6), which missed its first seven shots from the arc but finished 5-of-14, will meet either Kentucky or Utah in the regional final on Sunday. It is the fifth trip to the regional finals in seven years for the Spartans.
Michigan State took control in the opening minutes of the second half. After Duke's Shelden Williams hit two free throws and Daniel Ewing scored on a breakaway for a 36-32 lead, Alan Anderson highlighted a 16-3 run with three 3-pointers as the Spartans took a 48-39 lead with just under 12 minutes to play.
"His 3-pointers were huge," Duke coach Mike Krzyzewski said. "Anderson was terrific. I know Davis was good, but Anderson is the heart and soul of the team in my opinion. He was great in the second half."
Anderson, a senior, had six 3-pointers in his first two years and entered the game with 21 this season.
"I was only shooting 19 percent in the tournament, so I had to make them pay," said Anderson of the Duke defense allowing him open 3-point shots.
After a 3-pointer and a follow jam by Duke's Lee Melchionni, the Spartans responded with two layups by Maurice Ager, including a rousing one-handed fast-break dunk that rebuilt a 52-44 lead with 10:22 left.
Duke's J.J. Redick then hit a pair of 3-pointers - his first baskets in nearly 13 minutes - and two free throws, and Williams scored twice from the stripe with 7:10 remaining to pull Duke within 58-54.
Davis then took over. He scored eight points - all on the inside - over the next 4 1/2 minutes, including a 3-point play that fouled Williams out and pushed the Spartans' edge back to 69-63 with 2:41 left.
"I felt like I was jumping a little bit backward while I wasn't initiating any contact," said Williams of his fifth foul. "Unfortunately, it didn't happen like that."
"Davis' three-point play was huge," Krzyzewski said. "We had just gotten to within three points."
The 6-10 junior converted the first two of Michigan State's eight straight free throws in the final 65 seconds to seal the victory.
Davis finished with 20 points and 12 rebounds, including seven on the offensive end, and Anderson added 17 and eight for the Spartans, who outrebounded the Blue Devils, 38-33, and forced 21 turnovers - eight more than the Blue Devils' season average.
"We tried to tell them that they need 40 minutes of intense focus," Michigan State coach Tom Izzo said. "We had a few letdowns here and there, but we're getting to the point where I think we're spending a much higher percentage of the time really (playing hard)."
"Michigan State's defense was terrific, without traps to press the ball and force 22 turnovers" Krzyzewski said. "The first half in particular, we had 12 turnovers."
Ager scored 14 and Shannon Brown added 11 for the Spartans, who shot 42 percent (27-of-65).
"We really wanted to get after them and wear them out," Ager said. "At the end, we could tell they were a little bit tired, and we just kept after them and took the game to them the best we can. We ran as much as we could and took the ball to the hole, and it worked by getting to the line and getting fouls on Williams."
Williams had 19 points and nine rebounds and Ewing added 18 for Duke (27-6), which got knocked out in a regional semifinal for the fourth time in the last six years.
Redick, who scored 21 of his 29 points in the first half of Duke's win over Michigan State in November, scored 13 points on 4-of-13 shooting. He didn't get a shot for the first 9 1/2 minutes.
"We played four or five games on him and I thought we did a pretty good job on Redick," Izzo said. "What we tried to do was jump to him as soon as he got the ball."
The game was tied, 32-32, at the half. Duke, which didn't score from the field the last four minutes of the opening 20 minutes, never trailed, getting 13 points from Williams and holding Michigan State to 37 percent (13-of-35) shooting. But the Spartans, who got eight points and seven rebounds from Davis, stayed in the game by forcing 12 turnovers and holding a 9-3 edge in offensive rebounds.
The half didn't end without excitement. After Ager sank two free throws to tie the game with 4.2 seconds left, Duke inbounded to Sean Dockery, who was stripped at midcourt by Anderson, who drove in for a layup with three-tenths of a second remaining. But the clock never started until Dockery lost the ball, so the score was waved off after a discussion by the officials.