Lance Armstrong (noted by CJG, seconded by Joe S., thirded by Robert S.)

The act of needing only one ball to win a pinball game from any deficit.

Even though pinball games give you three or five balls to work with, the rules of some games are set up in such a way that any one ball could secure a victory.

One of the quirks of pinball is that any one ball can last an indeterminate period of time, as long as you have the endurance, the concentration and the perseverance to keep going.

One example of a Lance Armstrong is a ball wherein you score a huge number of points in a very short period of time. A ball that suddenly propels you to a win, where before it seemed as if you would surely lose. This can demoralize your opponents who now have quickly found themselves on the losing end.

Another example of a Lance Armstrong is a ball wherein you score a huge number of points over a very long period of time. This can also demoralize your opponents, who have been frozen out of the game, because they haven’t played for a while.

Example:
“Just Lance Armstrong this — one good ball, and you could put up some good points.” –CJG

(After hearing this term used by three different people in two separate contexts, this entry needed to happen.)