Connaughton went 7-of-12 from beyond the arc en route to 21 points for the Fighting Irish (19-8, 11-3 Big East), who have won eight straight conference games for the first time since the 2000-01 season. Connaughton also pulled down nine rebounds.
Jack Cooley recorded his fourth straight double-double with 18 points and 13 boards for Notre Dame, which has tied its best start in Big East play since becoming a conference member in 1995-96. The 2000-01 team was 11-3 before finishing the campaign with an 11-5 league mark in what was a 16-game conference regular-season slate.
Eric Atkins and Jerian Grant added 17 and 10 points, respectively, for the Irish, who are tied with Marquette for second place in the conference standings. Syracuse holds a two-game lead over both teams.
"What a night. Well, I'm really proud of our group," Notre Dame head coach Mike Brey said. "The second half we did a better job rebounding the basketball and keeping them to one and done situations."
The score was tied at 65 after Connaughton and Pinkston made three-pointers late in overtime.
Grant then made a three-pointer of his own to give the Irish a 68-65 lead with 1:28 remaining. Pinkston was way off the mark with a shot from beyond the arc at the other end.
Connaughton came through with another three-pointer to give Notre Dame a 71-65 margin. The Irish went 3-of-6 from the foul line in the final minute to secure the victory.
"Obviously it was a tough loss and a game you wish you never had to experience, but we have had a couple of those this year," Villanova head coach Jay Wright said. "We are paying our dues. Notre Dame made every big shot down the stretch and we missed every big shot. We got good shots, we just missed them."
Down by five, 10-5, early on, Villanova took control with a 28-5 run. Pinkston capped the surge with a jumper, making it 33-15 with 4:01 to go.
The lead reached 20 on Markus Kennedy's slam with 1:53 left. The Wildcats shot 48.4 percent from the floor and made four three-pointers in the first half en route to a 39-23 edge.
Trailing 46-32 with under 13 minutes remaining in regulation, Notre Dame ripped off seven straight points to make it a game. Atkins' layup cut the gap to 46-39 with 8:54 to play.
The Irish then used a late surge to take the lead. Down 56-47 with 4:26 left, the visitors went on a 13-0 run. Connaughton and Grant each made three- pointers during the burst, with Grant's trey giving Notre Dame a 60-56 edge with 59.2 seconds remaining.
Cheek made two free throws at the other end to make it a two-point game. After Grant missed a three-pointer, Maurice Sutton recorded a putback layup with 0.9 ticks left to send the game into overtime.
Villanova owns an 18-16 lead in the all-time series with Notre Dame, but the Irish won last year's tussle in South Bend, 93-72. Notre Dame made a school- record 20 three-pointers in that contest...The Irish went 12-of-31 from three- point range...Sutton had 12 points and 10 rebounds...Notre Dame has won its last four road games. It's the first time the Irish have won that many consecutive games on the road since they captured five straight during the 2000-01 season.