The Major League Baseball (MLB) postseason is one of the most anticipated sporting events each year. However, the structure and format of MLB playoffs can seem complex at first glance.
This guide aims to break down the different rounds, seeding procedures, and other key rules that determine how teams qualify for and advance through the MLB postseason tournament.
I. Overview of MLB Divisions and Qualifying Teams for Playoffs
MLB is split into two leagues – the American League (AL) and National League (NL). Each league contains three divisions: East, Central, and West. Within each division, teams play each other numerous times over the regular season to determine division winners. At the end of the 162-game regular season, the top six teams from each league (three division winners and three Wild Card teams) qualify for the postseason tournament. Division winners are seeded based on their regular season win-loss record, with the best record earning the #1 seed. The three Wild Card teams are also seeded #4, #5, and #6 based on their records. This divisional structure and six-team playoff format from each league ensures geographical rivals regularly play each other while also rewarding sustained excellence across each league. It creates compelling divisional and Wild Card races that extend fan interest into the late regular season.
II. Wild Card Round Format and Seeding
The Wild Card Round Format is a best-of-three series between the No. 3 seed (the division winner with the worst record) and the No. 6 seed (the Wild Card team with the worst record), and the No. 4 seed (the best Wild Card team) and the No. 5 seed (the second-best Wild Card team) in each league.
The higher-seeded team hosts all three games. The winners of the Wild Card Series advance to the Division Series, where they face the No. 1 seed (the division winner with the best record) and the No. 2 seed (the division winner with the second-best record) respectively.
The Seeding of MLB playoffs is based on the regular season records of the teams, with the division winners taking precedence over the Wild Card teams.
The teams are ranked from No. 1 to No. 6 in each league, with the No. 1 and No. 2 seeds receiving first-round byes. The seeding does not change after the Wild Card Series, so the No. 1 seed always faces the winner of the No. 4/5 series, and the No. 2 seed always faces the winner of the No. 3/6 series.
Here is a table that summarizes the Wild Card Round Format and Seeding of MLB playoffs:
| League | Seed | Team | Record | Opponent | Series Result |
|---|---|---|---|---|---|
| AL | 1 | Rangers | 97-65 | – | Bye |
| AL | 2 | Astros | 95-67 | – | Bye |
| AL | 3 | Red Sox | 91-71 | Blue Jays | Lost 1-2 |
| AL | 4 | Blue Jays | 90-72 | Red Sox | Won 2-1 |
| AL | 5 | Rays | 88-74 | Yankees | Won 2-0 |
| AL | 6 | Yankees | 87-75 | Rays | Lost 0-2 |
| NL | 1 | Braves | 104-58 | – | Bye |
| NL | 2 | Dodgers | 102-60 | – | Bye |
| NL | 3 | Cardinals | 92-70 | Diamondbacks | Lost 1-2 |
| NL | 4 | Diamondbacks | 89-73 | Cardinals | Won 2-1 |
| NL | 5 | Giants | 88-74 | Brewers | Won 2-0 |
| NL | 6 | Brewers | 86-76 | Giants | Lost 0-2 |
This format gives an advantage to higher seeds while also creating the possibility of lower seeds pulling off upsets. It has produced many memorable do-or-die games with playoff spots and seasons on the line.
III. Division Series Format and Seeding
The Division Series is the quarterfinal round of the Major League Baseball postseason.
Four series are played in this round, two each for both the American League and the National League.
The Division Series follows the Wild Card Series, where the winner of each league’s one-game playoff faces the top seed of their league.
The Division Series is a best-of-five series with the higher seed hosting the first two games and the fifth game, if necessary. The lower seed hosts the second and third games. The winner of the series advances to the League Championship Series.
The seeding for the six teams in each league is as follows:
| Seed | Team |
|---|---|
| 1 | Best league record |
| 2 | Second-best division winner |
| 3 | Third-best division winner |
| 4 | Best record among Wild Card teams |
| 5 | Second-best record among Wild Card teams |
| 6 | Third-best record among Wild Card teams |
The Nos. 1 and 2 seeds will receive first-round byes and advance directly to the Division Series. For the Wild Card Series, the No. 3 seed will face the No. 6 seed, and the No. 4 seed will face the No. 5 seed. The No. 1 seed will face the winner of the Wild Card Series between the Nos. 4/5 seeds, while the No. 2 seed will face the winner of the Nos. 3/6 series.
Here is a table that shows the possible matchups for the Division Series:
| ALDS | NLDS |
|---|---|
| No. 1 seed vs. No. 4/5 seed | No. 1 seed vs. No. 4/5 seed |
| No. 2 seed vs. No. 3/6 seed | No. 2 seed vs. No. 3/6 seed |
This format again rewards regular season success while still allowing some home games for the underdog.
IV. Championship Series Format
The Championship Series Format of MLB playoffs is the third round of the postseason tournament that determines the champion of Major League Baseball. It consists of two best-of-seven series, one for each league (American and National), in which the winners of the Division Series face each other.
The winners of the Championship Series advance to the World Series, where they compete for the Commissioner’s Trophy.
Here is a table that summarizes the Championship Series Format of MLB playoffs:
| League | Teams | Format | Home-field advantage |
|---|---|---|---|
| American League | Winner of ALDS between No. 1 seed and winner of Wild Card Series between Nos. 4/5 seeds vs. Winner of ALDS between No. 2 seed and winner of Wild Card Series between Nos. 3/6 seeds | Best-of-seven in a 2-3-2 format | Higher seed |
| National League | Winner of NLDS between No. 1 seed and winner of Wild Card Series between Nos. 4/5 seeds vs. Winner of NLDS between No. 2 seed and winner of Wild Card Series between Nos. 3/6 seeds | Best-of-seven in a 2-3-2 format | Higher seed |
In the ALCS and NLCS, the team with the better regular season record (i.e. higher seed) of the two receives home-field advantage for Games 1 and 2 as well as Games 6 and 7 if necessary.
Games 3, 4, and 5 are hosted by the lower seeded team. This 2-3-2 format for a best-of-seven series maximizes home games for the top seed while still giving the underdog a chance to steal a road win or two. It has produced many tense late-inning moments and unforgettable Championship-clinching victories.
V. World Series Format
Finally, the champions of the AL and NL face off in the best-of-seven World Series, with home-field advantage awarded to the league that won the All-Star Game that year. Like the LCS, the World Series follows a 2-3-2 format.
The team from the league that triumphed in the Midsummer Classic receives home field for Games 1, 2, 6, and 7. Games 3, 4, and 5 shift to the other league’s champion’s home ballpark.
Here is a table that summarizes the World Series Format in MLB:
| Round | Teams | Format | Home-field advantage |
|---|---|---|---|
| World Series | Winner of ALCS vs. Winner of NLCS | Best-of-seven in a 2-3-2 format | Team with the best regular-season record |
This format creates a fair and balanced structure for the Fall Classic while honoring the significance of the All-Star Game outcome in determining a slight initial advantage.
VI. Tiebreaker Rules
In the rare case of a regular season tie between division rivals or Wild Card contenders, a series of tiebreakers are in place to determine postseason seeding and qualification:
- Head-to-head record between the tied teams from the regular season
- Best winning percentage in intradivision games
- Best winning percentage in the last half of intraleague games
- Best winning percentage in the last half plus one intraleague game, etc.
- Most wins in intraleague games
- Coin flip
These tiebreakers provide a logical, step-by-step process to fairly evaluate teams’ true strengths against their direct competitors when their records are otherwise equal.
In conclusion, while complex at first glance, the MLB’s playoff structure and format has evolved into a balanced postseason tournament that maximizes drama, excitement and fan interest. The different rounds and seeding procedures reward top teams while still giving underdogs a chance, creating some of the most memorable moments in sports each October.