100-win history for Astros, Red Sox, Yankees

The Red Sox, Astros and Yankees have combined to make history. This is the first season ever in Major League Baseball in which there are three 100-win teams in the same league.
With the Bronx Bombers' 100th win of 2018 on Saturday, they joined Boston (107 wins) and Houston (103 wins) in reaching the century mark in the American League. The Red Sox were the first team to win 100 games this season, reaching that milestone on Sept. 12, while the Astros won their 100th game on Tuesday.

That should make for an action-packed postseason. The Red Sox would face the Yankees in the AL Division Series if the Yankees beat the A's in the AL Wild Card Game on Wednesday. If the defending World Series champion Astros beat the Indians in the other ALDS, they could face off against one of their 100-win counterparts in the AL Championship Series.
There are six other instances in which three total teams across the Major Leagues reached 100 wins during the same campaign -- including last season, when the Dodgers, Indians and Astros did it. But, until now, the three 100-win teams had never been in the same league.
Here are the other years that MLB had three 100-win teams:
2017: Dodgers (104 wins, NL), Indians (102 wins, AL), Astros (101 wins, AL)
2003: Braves (101 wins, NL), Giants (101 wins, NL), Yankees (101 wins, AL)
2002: Yankees (103 wins, AL), A's (103 wins, AL), Braves (101 wins, NL)
1998: Yankees (114 wins, AL), Braves (106 wins, NL), Astros (102 wins, NL)
1977: Royals (102 wins, AL), Phillies (101 wins, NL), Yankees (100 wins, AL)
1942: Cardinals (106 wins, NL), Dodgers (104 wins, NL), Yankees (103 wins, AL)