If, prior to teeing off from the teeing ground of the first hole of any stipulated round, a player informs his fellow players of his intention of replaying one unsatisfactory tee shot and secures from them their clearly stated consent to this procedure, he may, upon hitting a flawed drive, put into play a revisional ball (mulligan) without assessing a stroke or incurring any penalty, under whichever of the following conditions of permissible replay has been mutually agreed to:

1. On the first tee of any 9-hole or 18-hole course, or
2. On the first and the tenth tees of any 18-hole course having two distint 9-hole layouts, provided play is suspended, however briefly and for whatever purpose, at the conclusion of play on the first 9 holes, or
3. On the tee of any one hole, regardless of its position in the sequence of holes.

However, if a player elects to hit a revisional ball, he must play that ball, even if it comes to rest in a lie substantially worse than that occupied by his original ball, unless the option of playing the better of the two balls has itself also been separately endorsed by all the players in the playing group (see Exception 2, Preferential Ball).