Born in Cleveland, Ohio, he grew up in a small town in Cincinnati, OH North College Hill. Where he played basketball in the neighborhood growing up. Mack graduated in 1988 from St. Xavier High School in Cincinnati, Ohio, where he was named 1987-88 Cincinnati Post Metro Player of the Year.
He continued on to the University of Evansville, where he played basketball for two seasons. He transferred to Xavier in 1990, where he played his final two seasons of eligibility (after redshirting one for transfer rules), and graduated in 1992 with a B.A. in Communication Arts. He is married to Christi Mack (Hester), a former University of Dayton guard (1996–2000). They have three children and reside in northern Kentucky.
When Miller moved to the University of Arizona in 2009, on April 15, 2009 it was announced that Mack would replace Miller as Xavier head coach. The first top 25 ranking by a Mack-led Xavier team was March 1, 2010 when it made its season debut in the Associated Press Poll at #25. During that season, the Jordan Crawford-led Musketeers won the Atlantic 10 Conference and advanced to the NCAA Sweet 16. The Musketeers had question marks heading into the next season, yet Mack guided the team to its fifth consecutive Atlantic 10 Championship before falling to Marquette in the first round of the NCAA tournament. During both of these years Mack earned Atlantic 10 Coach of the Year award. Heading into the 2011-2012 campaign the Musketeers were slatted to be one of the top teams in the country. With senior All-American Tu Holloway returning, Mack and Xavier were on the cusp of a special year. Xavier got off to a great start and a #7 ranking before the brawl with their in-city rival UC Bearcats derailed the Musketeers. Mack's squad did not win the Atlantic 10 Tournament title in 2012 but was able to advance to the NCAA Sweet 16 with wins over the Notre Dame and Lehigh.
National champion Postseason invitational champion Conference regular season champion Conference regular season and conference tournament champion Division regular season champion Division regular season and conference tournament champion Conference tournament champion