This comes from the 2013 Luci Bonneau Doubles in Houston, where bowler Troy Walker was one strike away from a perfect 300 game when disaster struck.
As his ball hurtled toward the pins, the arm rake of the pinsetter lowered and deflected his ball into the gutter.
He got a do-over, but he couldn't get a strike and finished with a 297.
Awful (h/t SB Nation):