Busch led the opening 74 laps until he was passed by Dale Earnhardt Jr. Busch 's No. 18 Camry steadily lost position as the car 's handling worsened .
Busch is sunday 's pole sitter and Saturday 's Xfinity Series race winner .
Busch , Sunday 's pole sitter and Saturday 's Xfinity Series race winner , led the opening 74 laps until he was passed by Dale Earnhardt Jr. Busch 's No. 18 Camry steadily lost position as the car 's handling worsened .