In a Hoosier State showdown, No. 2 seed Purdue (29-6) faces No. 10 Butler (21-13) in Detroit.
In the nightcap to the entire round of 32, No. 5 seed West Virginia (25-10) renews its rivalry with No. 13 Marshall (25-10) far from the Mountain State, at San Diego State's Viejas Arena.
Marshall's first-ever NCAA tourney win, an 81-75 thriller against No. 4 seed Wichita State, gave Thundering Herd coach and alum Dan D'Antoni the chance to lobby for the resumption of a rivalry that ended after the 2015 game, mostly because West Virginia and its coach, Bob Huggins, felt there wasn't anything to gain anymore in a series the Mountaineers lead 33-11.
While the coaches had strong words in the rivalry's final seasons, the players are simply looking for a good game.
"I think it's an exciting time for the state," Thundering Herd guard Jon Elmore said Saturday. "You talk to everybody back home, half of the state's population is probably flying out here right now for the game."
One of those fans likely headed to San Diego is Jarrod West, who banked in a 3-pointer with less than a second left to give West Virginia a 75-74 second-round win against Cincinnati in 1998, when Huggins was the Bearcats' coach.
His son, also named Jarrod, is a freshman guard for the Thundering Herd.
"He's excited," the younger West said of his dad. "I wouldn't say he's very conflicted at all, really. I think he's definitely rooting for us really hard."
The younger West said West Virginia recruited him "a little bit, maybe not as much as I think I should have been."
And the rivalry? "We try to stay out of the politics and all that stuff," West said. "That's not our responsibility. Our responsibility is to come out and be ready to play."
West Virginia's players feel the same way.
"Just another game," forward Esa Ahmad said a day after the Mountaineers beat No. 12 seed Murray State 85-68.
"Don't matter," guard Jevon Carter said. "This is March. We're here to win a national championship. It just happens that we're matched up against Marshall. Don't matter who it is. We're going to come to play and do our best and get a win."
While D'Antoni would like to see the rivalry renewed, Huggins, a West Virginia alum, thinks too much is being made about it.
"We don't really cross," Huggins said, noting that the schools are on opposite ends of the state. "You don't want to make it out to be Duke-North Carolina. It's not that at all."
FRIENDLY FOES?: The East's other in-state rivalry Sunday doesn't appear all that testy.
Purdue and Butler played earlier this season, with the Boilermakers prevailing 82-67. Purdue had actually lost five straight in the series before that, but prior to that streak, the Bulldogs dropped 12 in a row against the Boilermakers.
Second-seeded Purdue takes on 10th-seeded Butler in Detroit - a matchup within reasonable driving distance for fans of the two Indiana schools.
"We're familiar with them, obviously being so close. A lot of those guys are from Indy and I think in the summertime we work out with them, open gyms and things like that," Purdue guard Dakota Mathias said. "I got pretty close with Kelan Martin this summer, just working out together. So we definitely follow their progress and how they've been doing."
Martin is Butler's leading scorer and had 27 points in a first-round win over Arkansas.
The Bulldogs will try to avoid a repeat of their offensive performance in December, when they shot 7 of 33 in the first half against Purdue.
"Some teams can't pressure without giving up great looks," Butler coach LaVall Jordan said. "They're really well coached, where they can apply a ton of pressure, ball pressure on the perimeter and still keep you from getting wide open, drive-kick 3s. A lot of that is due to they've got rim protectors at the basket. When (Isaac) Haas is in there and the other kid is in there, he blocks shots, so you're forced to drive into him."
It doesn't sound like the 7-foot-2 Haas will be in there after he broke his elbow in a win over Cal State Fullerton on Friday, but by Saturday there seemed like at least some possibility of a return. Backup Matt Haarms is 7-foot-3, so Purdue can still put plenty of size on the court.
AP Sports Writer Noah Trister in Detroit contributed to this report.
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