Bain's basket came off Duke's fifth turnover in the extra session and ended the Blue Devils' 150-game homecourt winning streak in nonconference games.
Duke became the third No. 1 team to lose this season, and the second one to do so on its homecourt. The Blue Devils (6-1) scored only two points in overtime.
Stephen F. Austin (5-1) was led by Kevon Harris' 26 points. Cameron Johnson added 16 points. Vernon Carey Jr. posted 20 points for Duke, with Tre Jones notching 17 and Matthew Hurt and Cassius Stanley each supplying 15.
The Spartans nearly coughed up a 28-point lead, then rallied in the final minutes to hold off the Bulldogs in the consolation bracket at the Maui Invitational in Lahaina, Hawaii. Michigan State (4-2) moves on to face UCLA on Wednesday in the fifth-place game. Georgia (4-2) will battle Chaminade for seventh place in the eight-team event.
The Spartans built a 21-point halftime lead behind 24 combined first-half points from Cassius Winston and Aaron Henry. The duo ended up with 28 and 14 points, respectively, while Xavier Tillman added 15 points -- including a critical 3-pointer with less than three minutes remaining and Georgia threatening.
The Bulldogs fell behind 61-33 with 16:26 to go in the second half, but Anthony Edwards led a rollicking comeback. The ballyhooed freshman scored a career-high 37 points to power the rally, 33 of which came in the second half. He threatened Adam Morrison's Maui Invitational record of 43 points with an array of baskets, including seven 3-pointers.
David McCormack led four Kansas players scoring in double figures, and the Jayhawks beat the Cougars to advance to the championship game of the Maui Invitational in Lahaina, Hawaii. Kansas (5-1) will face Dayton for the title. The Cougars (4-3) will oppose Virginia Tech in the third-place game.
Kansas' interior duo of McCormack and Udoka Azubuike paced the Jayhawks to a 42-18 edge on points in the paint. Azubuike recorded 11 points and 10 rebounds.
Ochai Agbaji scored 14 points for Kansas, and Devon Dotson added 13 points and eight assists. TJ Haws led BYU with 16 points, and Kolby Lee scored 13 points. Jake Toolson, the Cougars' leading scorer on the season at 16.7 points per game, finished with seven points on 3-of-9 shooting.
Guard Samir Doughty scored 22 points and center Austin Wiley added a season-high 18 in dominating the game inside as the Tigers pulled away in the second half to defeat the Spiders in the championship game of the Roman Legends Classic in New York.
Wiley also collected eight rebounds and blocked two shots for the Tigers (7-0), who outscored the Spiders 45-30 in the second half after trailing 35-34 at halftime.
The Spiders (5-1) got 14 points from forward Grant Golden and 12 each from guards Jacob Gilyard and Nick Sherod, but couldn't contend with the more physical Tigers inside. Auburn had a 44-34 rebounding advantage with 18 at the offensive end.
Tyler Bey scored 18 points, grabbed 10 rebounds and blocked four shots as the Buffaloes rallied from a 12-point, second-half deficit to defeat the Tigers in the championship game of the MGM Resorts Main Event in Las Vegas.
D'Shawn Schwartz scored 12 points, Evan Battey finished with 11 points, and McKinley Wright IV scored all 10 of his points in the second half for the Buffaloes (5-0). Colorado snapped a five-game losing streak to Atlantic Coast Conference teams dating back to a 1991 win over Wake Forest.
Junior Aamir Simms tied his career high with 23 points, Tevin Mack finished with 11 points and nine rebounds, and John Newman III added 16 points for Clemson (5-2). The Tigers fell to 1-11 all-time against Pac-12 teams.