Who have been the best and worst playoff teams?

Yesterday, the Minnesota Twins extended their MLB record streak, losing their fifteenth consecutive playoff game. For context, no National League team has lost 15 straight in a single season for over forty years: the last to do so were the Atlanta Braves in 1977 [the Cubs did lost 16 straight, but that was split between 1996 and 1997]. It got me wondering, which franchises have done the best and worst overall in the post-season? The answer proved a bit tricky to find, since Baseball Reference’s Play Index doesn’t let you sum play-off records for teams across multiple seasons. I’ll spare you the details, but there was a spreadsheet involved. With multiple tabs. I may even have had to use... [gasp!] pivot tables.

Anyway, I crunched the numbers, setting the starting point at 1998. That was the point at which MLB reached its current 30 teams, so every franchise has had the same number of opportunities to compete, for a total of 21 seasons [I’ve not included this year, being still under way]. Of course, opportunity does not equal success. But let’s look at the different ways you can slice the data. For each category, I’ll give the top and bottom three, along with the Diamondbacks’ position in the rankings.

Playoff appearances

• 1. Yankees - 17
• 2. Braves, Cardinals, Red Sox - 12
• 14. D-backs - 6
• =29. Blue Jays, Mariners, Royals - 2
• 30. Marlins - 1

That’s a startling achievement for New York, making the playoffs more than three-quarters of the time, but there are three other teams who have also been there more often than not. Not listed are the Dodgers, who own the current longest active streak, having made the post-season seven years in a row, including this season. At the other end, we find the Marlins. whose sole appearance was in 2003. Though that did go quite well. It isn’t the longest absence though, as the Mariners are now at 18 consecutive playoff-less seasons and counting. That’s the longest in any of the major sports. Though it is harder to reach the post-season in MLB than, say, the NHL, where more than half the teams make it.

Wins per playoff season

• =1. Marlins, Royals - 11.00
• 3. Giants - 6.86
• =19. D-backs - 3.00
• 28. Pirates - 1.00
• 29. Twins - 0.86
• 30. Reds - 0.67

This is the “bang for your buck” category, highlighting teams that do the most when they reach the post-season. Florida and Kansas City are the champions here. As mentioned above, the Marlins won it all, their only time playing on through into October. The Royals’ two appearances saw a World Series win and a World Series loss in seven, with 11 victories each time (the latter having an extra W through the wild-card game). Arizona rank a bit below average, having managed only one win since 2007. But at least we’re not Minnesota or Cincinnati. For both of them aspire to averaging even a mere “one and done” over the last twenty-plus seasons.

Playoff wins

• 1. Yankees - 93
• 2. Cardinals - 65
• 3. Red Sox - 62
• 16. D-backs - 18
• =27. Orioles, Twins - 6
• 29. Pirates - 3
• 30. Reds - 2

Unsurprisingly, most of the teams which play in a lot of post-seasons, have accumulated a lot post-season wins. The exception is Atlanta, who barely sneak into the top 10 in this category, with just 26 victories in their dozen playoff campaigns. That’s fewer wins per post-season than the Rockies or Padres. For Arizona, the 2001 campaign obviously dominates: 11 wins there, with seven across all other years combined. But pity poor Reds fans: just two play-off game victories and ZERO play-off series wins. You’ve got to go all the way back to 1995 to find the last time Cincinnati last got to celebrate a post-season series victory, even a one-game wild-card one. With only 75 wins this season, that drought may continue.

Win percentage

• 1. Royals - .710
• 2. Marlins - .647
• 3. White Sox - .632
• 17. D-backs - .450
• 28. Nationals - .368
• 29. Reds - .222
• 30. Twins - .214

Only nine teams actually have a winning post-season record from 1998-2018. That’s because they include almost all the most frequent participants, save the Braves (as noted above) and the Dodgers. All three teams with 100+ games (Yankees, Red Sox, Cardinals) are above .500. As for the White Sox, the majority of their play-off series have ended in sweeps, one way or another. Oakland GM Billy Beane may reckon his shit doesn’t work in the post-season, but there are five teams with lower winning percentages than the A’s. You are probably not surprised by who is in last place, and it’s potentially going to get even worse after this year, unless they can pull out a win tomorrow.

Below is the chart with the above information for all 30 teams (sorted by W%), so you can look at it yourself and come to your own conclusions.