James Bell added 19 points and Darrun Hilliard contributed 15 for Villanova (2-0). Arcidiacono also had six assists.
D.D. Scarver led four Thundering Herd (1-1) players in double figures with 22 points.
“I thought Ryan was just great at the point,” Villanova coach Jay Wright said. “I think he came in here from Day One knowing exactly what we wanted to do, and he has a very high basketball IQ.”
Arcidiacono missed his senior season of high school due to a back injury that required surgery last December. He spent much of last season at Villanova practices and games, and he said that helped him prepare for the jump to college.
“I wish I could have played and everything, but coming to all of these games and seeing the intensity of every practice every game (helped),” he said.
Marshall got as close as two points twice in the second half, the last coming with exactly four minutes remaining when Chris Martin knocked down a 3-pointer to make it 70-68. But Bell hit a 3-pointer, Hilliard drained two free throws, and Arcidiacono hit one on a 6-0 Wildcats run that gave Villanova the cushion it needed, 76-68 with 55 seconds left. The Herd didn’t score in the last four minutes.
“I was really just watching to see what happened,” Wright said. “Either they’re going to take a lead, or we’re going to have the guts to fight through it. I like that we stayed tough. I thought we executed well down the stretch.”
Arcidiacono, from nearby Langhorne, Pa., was stellar in the first half when he made 5 of 8 shots from the field, including 4 of 7 from 3-point range. He also added four assists, including a nifty left-handed pass to Hilliard on a 2-on-1 break that ended with a Hilliard dunk.
Arcidiacono ended 6-for-11 from the field, including 4-for-9 from beyond the arc.
“I felt good shooting the ball in warmups,” he said. “The first couple shots went down. Coach just said be aggressive and look for my shot, and luckily they went down.”
Marshall coach Tom Herrion thought his team gave too many easy looks to the Villanova freshman.
“We did a poor job on (Arcidiacono) early,” he said. “That’s unacceptable. I know he’s a talented player, but we contributed mightily.”