The start of the second half of the 2018 Lucas Oil Pro Motocross Championship turned the 450 Class title fight upside down as point leader and defending champion Eli Tomac endured through an arduous afternoon at RedBud. His misfortune opened the door for Marvin Musquin to take his second win of the season and move atop the championship standings. In the 250 Class, point leader Aaron Plessinger extended his advantage with his third victory of 2018.