(LOUISVILLE) - Louisville players and coach Chris Mack cared more about protecting the basket against Michigan than defending their new perch atop the rankings. Fulfilling that priority helped the Cardinals succeed in their season debut as the nation's No. 1 team. Jordan Nwora had 22 points and 12 rebounds, and Louisville held No. 4 Michigan to a season-low 26% shooting mark for a 58-43 victory Tuesday night in its first game since returning to No. 1. The Cardinals (8-0) shot just 37% but their defense stifled Michigan (7-1) much of the night as they earned a signature victory in the Big Ten/ACC Challenge one day after claiming the top spot in the AP Top 25 for the first time in six years. Louisville answered the Wolverines' 6-0 spurt that got them to 30-26 with a 10-0 run keyed by six points and a couple of pivotal rebounds from Nwora, who tied his season high on the boards. The Cardinals also kept the Wolverines and first-year coach Juwan Howard from adding another top-10 upset to the ones that helped them enter the Top 25 and match Kansas (1989) for the biggest jump from being unranked in the 70-year history of the poll. Jon Teske had 18 points and 10 rebounds for the Wolverines, who were seeking their first victory over a No. 1 team since beating Duke 81-73 at home on Dec. 13, 1997. Zavier Simpson had 9 points for the Wolverines.