Marquette had tied the game at 88 when Koby McEwen hit a stepback 3-pointer and turned it into a four-point play with 25 seconds to go.
Xavier ran the clock down and Paul Scruggs drove into the lane to attempt a floater in the closing seconds. Marquette's Dawson Garcia blocked the shot and Kunkel beat a teammate to it near the top of the key. He took a dribble left to find space and launched a shot over two lunging defenders that that swished at the buzzer. He back pedaled into his own lane before being mobbed by his teammates under the basket.
There were 11 ties and 13 lead changes and neither team had a lead that reached double figures. Marquette shot 55% and Xavier shot 54%.
Scruggs scored 29 points to lead the Musketeers (8-0, 1-0 Big East Conference), who had not played since Dec. 9. Kunkel, a transfer from Belmont who expected to sit out this season, added 22 points and Nate Johnson had 14.
Garcia and McEwen both had 20 points for the Golden Eagles (5-4, 1-2). Theo John added 14 points.
Xavier takes on Creighton on the road on Wednesday. Marquette plays Villanova at home on Wednesday.
For more AP college basketball coverage: https://apnews.com/Collegebasketball and http://twitter.com/AP--Top25
Elements of this story were generated by Automated Insights, http://www.automatedinsights.com/ap, using data from STATS LLC, https://www.stats.com
Roddy scores 22 to carry Colorado St. past Air Force 74-44
— David Roddy had 22 points and 12 rebounds as Colorado State easily beat Air Force 74-44 on Monday night.
No. 17 Oklahoma State completes sweep of No. 16 Oklahoma
— Cade Cunningham scored 13 of his 15 points in the final 10 minutes to help No. 17 Oklahoma State defeat No. 16 Oklahoma 79-75 on Monday night, completing a sweep of two games in three days against the rival Sooners.
NCAA tournament Bubble Watch: Loyola Chicago inches closer to tourney return
Loyola Chicago made it to the Final Four in 2018. Three years later, the Ramblers are in position for a return to March Madness.