Oregon and Notre Dame entered the group, joining Texas A&M and LSU, with the Tigers and Aggies the two holdovers from his most recent list of finalists. Though schools like TCU, Texas and Clemson have since fallen out of Mack's top schools, the fact that A&M and LSU are still there shows they're a step above the others.
"Definitely," Mack said. "They're still ahead of everybody else in my top four."
LSU first jumped on Mack's radar this summer, when the Tiger coaches extended him an offer. Since then, LSU coaches Frank Wilson and Brick Haley have led the recruiting charge to land the No. 3 overall junior prospect.
The Aggies were Mack's leader before the Tigers came calling, and now Mack says those two teams are still tied atop his list.
Mack will later this month get a couple opportunities to start comparing A&M and LSU. Mack will travel down to College Station on Oct. 19 when the Aggies face Auburn, his first trip to the Aggies' campus since the summer.
The next week, Mack will make his first trip to Baton Rouge for the Tigers' Homecoming game against Furman. That date coincides with Mack's bye week, so he said he'll come down the Friday before the game and get the full tour of campus and get to better know the coaching staff.
Mack did get to see the Tigers play in person when he saw the season opener against TCU in AT&T Stadium. Since then, Mack said he's had a close eye on the Tigers.
"I've been paying attention to how they've been doing along the defensive line. I just like the style they play. I really like playing in the 4-3."
Mack also will likely make a return trip to LSU when the Tigers face his other top team in Tiger Stadium. Those visits could go a long way in helping Mack decide where he'll end up.
"That's exactly what I'm trying to do," Mack said. "It's going to be big. Those comparisons will help, especially when Texas A&M plays LSU."
Though A&M and LSU have the lead, Mack said both Oregon and Notre Dame are in consideration.
The Irish only officially extended him an offer last week, so the interest there is still relatively new. He saw them play in-person Saturday against Arizona State in AT&T Stadium. Mack said he's mostly been in contact with ND co-defensive coordinator Kerry Cooks.
During the game, Mack closely watched ND's start DT.
"I was really just watching Louis Nix and how he was playing," Mack said. "Coach Cooks told me I reminded him of Nix. So I wanted to see what he was talking about…I do [see the comparison] in how he gets off the ball and handles double teams…
"[I like] their fan base. I've been talking with Coach Cooks, and we're developing a good relationship. They're pretty cool guys. I'm going to talk to Coach [Brian] Kelly too."
As for the Ducks…
"It's Oregon," he said. "They're one of the top teams in the country. They're winning. And the jerseys of course, plus they have the best facilities in the world. I just want to build a relationship with their coaching staff too.
Mack has mentioned the possibility of shutting it down after his junior season. That still remains a possibility, though he may wait a little while longer than that.
"I could see myself deciding at the end of my season," Mack said. "But I'd like to visit Notre Dame and Oregon first. But it could be at the end of the season."
What are LSU's chances of landing Mack?