LEXINGTON, KY. ? Kent State can’t stop springing surprises.

The 10th-seeded Golden Flashes played smothering defense and slowed the tempo at every opportunity Thursday night, defeating No. 3 Pittsburgh, 78-73, in overtime in the South Regional semifinals.

Kent State (30-5) had never advanced beyond the second round of the NCAA Tournament before this year. Now it’s one victory away from the Final Four after knocking off higher-seeded Oklahoma State, Alabama and Pittsburgh to stretch the country’s longest winning streak to 21 games.

Antonio Gates scored 22 points and Trevor Huffman added 17 for the Golden Flashes, who made six straight free throws in the extra period against the Panthers (29-6).

“Our experience really paid off for us tonight. We never panicked,” said Huffman, one of four seniors on the team. “We’re still trying to reach that perfect game. We don’t want to stop here. We have a long way to go.”

Kent State plays fifth-seeded Indiana in Saturday’s regional final. The Hoosiers upended defending national champion and top-seeded Duke 74-73.

Brandin Knight, the Big East’s co-player of the year, and Julius Page each scored 18 for the Panthers, who were trying to reach the final eight for the first time since 1974.

“They played with poise down the stretch and we had to execute,” said Kent State first-year coach Stan Heath, an assistant to Tom Izzo on Michigan State’s 2000 national champions. “We had to make big shots and we did it.”

Pitt came into the game with a reputation for stifling defense, but the Golden Flashes showed from the opening moments that they could put the clamps on, too.

Kent State forced 17 turnovers  11 in the first half  and made it hard for Knight and Page to get open looks on the perimeter.

Knight tied the game at 66 with 52 seconds remaining in regulation. Following a Kent State turnover, Page’s long 3 from the corner bounded off the rim as the buzzer sounded, sending the game to overtime.

Gates hit a jumper inside to open the extra period, and Ontario Lott matched it with a basket at the 4-minute mark.

Pitt went up 71-70 on Jaron Brown’s free throw with 1:11 to play. From that point, Huffman made a high-banking layup off the glass, and Gates and Andrew Mitchell each added two free throws to push the margin to 76-71 with 21 seconds to play.

Mitchell, only 3-of-16 from the field for 12 points, added two more free throws in the closing seconds to seal the victory.

But don’t call Kent State a Cinderella team  one sign in the stands said it all: “We don’t wear slippers … we wear Nikes.”

Kent State led 29-23 at halftime, but Pitt soon closed the gap and eventually went up 45-43 on Donatas Zavackas’ three-pointer midway through the second half.

From that point, each team would surge ahead by two or three points, only to see the other recover and regain the lead.

Gates’ jumper put Kent State up 59-53 with 51/2 minutes to play, but Knight’s three-pointer keyed a 7-0 run to put the Panthers up 60-59 with 3:35 remaining.

Down 66-62 at the 2-minute mark, Pittsburgh forced OT by shutting out Kent State the rest of regulation, while Page hit a layup and Knight scored inside to tie the game at 66.

Pitt’s defense gave up just 60 points a game during the season and an average of only 52 in its tournament victories over Central Connecticut State and California.