Practice at the new track, which is built in downtown Detroit around GM’s Renaissance Center headquarters, was plagued by a succession of red and yellow flags as drivers struggled with their braking stability on the bumpy and twisty 1.7-mile layout.
Traffic also caused a huge issue, with Andretti Autosport’s Colton Herta claiming that Saturday's 45-minute practice period was the only session he’s ever done where he didn’t get to complete even one clear lap.
