when a team is ahead by at least 15 runs. The mercy rules applied to the round-robin (now double-elimination) matches only, not to the semi-finals or final. In a six-inning game such as Little League Baseball and Softball, rules call for the game to end if the winning team is ahead by 15 runs after three innings played or 10 runs after four innings played by the trailing team. In a seven-inning game at the intermediate level or higher, the corresponding run rule is applied for 15 runs after four innings, or 10 runs after five innings. Little League refers to this rule as the run rule, instead of the mercy rule. Softball rules are different for fast/modified fast pitch and slow pitch. In WBSC-sanctioned competitions, the run-ahead rule (the WBSC terminology) is, for fast or modified fast pitch, 20 runs after three innings, 15 after four, or 8 after 5. In slow pitch, the margin is 20 runs after four innings or 15 after five. The NCAA has also adopted the rule. In regular season or conference tournament NCAA and NAIA college baseball, the IBAF rule may be implemented. Most NCAA conferences limit the rule to the final day of a series, for travel reasons, or primarily during conference tournaments where four to five games are played in a day, in order to allow the next game to start. The rule is not allowed in NCAA tournament play (regionals, super regionals and College World Series), in which all games must be at least nine innings. In NCAA softball, the rule is invoked if one team is ahead by at least eight runs after five innings and, unlike with college baseball, applies in the NCAA tournament as well with the exception of the championship series. In American high school softball, most states use a mercy rule of 20 runs ahead in three innings or 10 in five innings. (In either case, if the home team is ahead by the requisite number of runs, the game will end after the top half of the inning.) Most state high school associations (where games are seven innings) use the IBAF Women's rule after five innings have been played by the trailing team; some associations further the rule by ending a game after either three or four innings if the lead is at least 15 runs. For softball, the rule is 12 after three