Supercross racing took a huge hit in 2015 when four-time champion Ryan Villopoto unexpectedly retired. Two years later, four-time champion Ryan Dungey put up his kickstand for good.
Two of the sport's biggest names and greatest champions gone, leaving a gap that could have sent the sport on a downward spiral.
Instead of crashing, Supercross has revved forward with bigger crowds and television audiences, thanks to a talented new crop of riders.
"It's funny, every time a champ like Villopoto or Dungey steps away, kind of leaves that void, you worry a little bit about who's going to fill it or if it will be filled," said Dave Prater, director of operations at Feld Entertainment, which runs AMA Supercross.