Dale Earnhardt Jr. hit a wall in turn two of his practice lap Friday at Michigan International Speedway in preparation for Sunday's Sprint Cup Series Pure Michigan 400 and will start in back.
Jimmie Johnson, the current series points leader, changed engines Friday and will also start in back.
George Sipple of the Detroit Free Press has the details:
“The guys saw something in warm up this morning and we were trying to sort through it before practice started," Johnson said. "They took a deeper look at things right before practice started and decided to change it. We probably could have run some of this practice, but I think we had to change the engine regardless, but we didn’t want to oil the track or create an issue and crash our car."
Earnhardt has tested his backup car at MIS, back in June.
Sipple also talked to Earnhardt Jr. about how winning at Michigan International in June helped give him confidence for Sunday's race.
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