Most days, there will be either one or three interleague games as the average number of interleague games per day will be 1.68 [(20 interleague games per team x 30 teams in MLB)/(183 total days in baseball season, including off days, but excluding the All-Star break)/2 teams per game]. With 15 teams in each league, the number of interleague games is almost always odd, with exceptions based on when teams from each of the AL and NL have the same off day. Doubleheaders and make-up games also apply should a rainout or other extended delay requires one or more games to be postponed.