But Arcidiacono opened the overtime scoring with two free throws. Later he fed center Daniel Ochefu for a bucket and added a driving layup of his own to make it 86-79. Marquette never got closer than five the rest of the way.
After missing 4 of 6 free throws during a key span in the final 1:11 of regulation, the Wildcats made their last four of regulation and all four in overtime.
Guard James Bell scored a career-high 30 as 'Nova (17-2, 6-1 Big East) cleared from its mouth the bitter taste of a 28-point home loss to Creighton on Monday. Arcidiacono finished with 20 points, and Darrun Hilliard matched that total.
Davante Gardner had 29 for Marquette (11-9, 3-4).
"That was a great college basketball game," Villanova coach Jay Wright said.
Arcidiacono made sure the result had Wright seeing the positives as the Wildcats dodged what could have been a demoralizing defeat.
"To have a point guard like that who wants the ball in his hands, makes the right decisions when the pressure's on," Wright said, praising his team's floor leader. "He's a special player."
Mayo's three tying free throws came after a foul by Arcidiacono, who fought past a pick but then made contact. After a timeout, Tony Chennault's driving layup was wiped away by a charging call.
So the Wildcats huddled before overtime. But they never doubted themselves.
"Our guys are good at that," Wright said of his players' getting off the deck. "We've got great leadership in James Bell, Tony Chennault, and Arcidiacono. They were saying, 'Next play.' "
They made all of the "next plays" in overtime.
"I felt good all game, and I just wanted the ball in my hands," Arcidiacono said. "If we were going to go down, I wanted it to be on my shoulders. I think I did a pretty good job of finding some guys and getting them in the right spots to score."