It almost seems impossible—especially on the PGA Tour. In the final round of the Sentry, Will Zalatoris and Cam Davis, playing in the same group, were penalized two strokes for playing the wrong golf ball on Kapalua’s par-5 15th.

Neither player realized the error until they reached the green. The penalty for playing the wrong ball is two shots, so the players had to return to the spot where they hit the incorrect golf balls and play from the correct spot.