The Major League Baseball (MLB) season schedule generally consists of 162 games for each of the 30 teams in the American League (AL) and National League (NL), played over approximately six months – a total of 2,430 games, plus the postseason. The regular season runs from late March/early April to late September/early October, followed by the postseason which can run to early November. The season begins with the official Opening Day, and, as of 2018, runs 26½ weeks through the last Sunday of September or first Sunday of October. One or more International Opener games may be scheduled outside the United States or Canada before the official Opening Day. It is possible for a given team to play a maximum of 22 games in the postseason in a given year, provided the team is a wild card and advances to each of the Division Series, Championship Series, and World Series with each series going the distance (3 games in the Wild Card series, 5 games in the Division Series, 7 games each in the League Championship Series/World Series). The regular season is constructed from series. Due to travel concerns and the sheer number of games, pairs of teams are never scheduled to play single games against each other (except in the instance of making up a postponed game, or more rarely, a one-game playoff to determine a postseason berth); instead they play games on several consecutive days in the same ballpark. Most often the series are of three or four games, but two-game series are also scheduled. Teams play one mid-week series and one weekend series per week. Depending on the length of the series, mid-week series games are usually scheduled between Monday and Thursday, while weekend games are scheduled between Thursday and Monday. Beginning in 2018, teams start and end their season on a weekend for 26½ weeks. Due to the mid-week all-star break in July, teams are scheduled to play 27 weekend series and 25 mid-week series for 52 series (24 divisional series, 20 inter-divisional series, 8 inter-league series). A team's road games are usually grouped into a multi-series road trip; home series are grouped into homestands. Note that rainouts and other cancellations are often rescheduled ad hoc during the season, sometimes as doubleheaders. However, if two teams are scheduled to meet for the final time in the last two weeks of the season, and the game is