Winning the World Series once is a difficult enough task. But to repeat? That’s a hill no team has been able to climb for quite some time.

When the Astros fell to the Rangers in the 2023 American League Championship Series, that made it 23 consecutive seasons in which MLB has not had a repeat champion -- easily the longest such streak in history. In fact, the NFL, NBA and NHL have never seen one that long, either.

From 1998-2000, the dynastic Yankees of Derek Jeter, Mariano Rivera and Joe Torre won three championships in a row. It was the 14th time a team had captured consecutive World Series since the event was first held in 1903, but nobody has managed that feat since.

As the Astros are now well aware (they also were unable to pull it off in 2018), repeating is no easy task. Only two of the previous 23 reigning World Series winners returned to the Fall Classic the next year. Here is a look back at each of those 23 clubs, how they fell short, and who took their place.

2023: Astros (Lost in AL Championship Series)
New champion: Rangers
The Astros were dangerously close to missing the playoffs entirely in 2023. After clinching a playoff berth in Game 161, Houston took the AL West division on the final day of the season -- ending the year in a tie with the Rangers with a 90-72 record but holding the divisional tiebreaker advantage. As a result, the Astros had a first-round bye before beating the Twins in the ALDS. In a case of sweet revenge, the Rangers beat the Astros in the decisive Game 7 of the ALCS to send Texas to a victorious World Series appearance.

2022: Braves (Lost in NL Division Series)
New champion: Astros
Early in the season, it looked like the Braves might struggle to make the postseason at all, finishing May at 23-27 and 10 1/2 games back in the NL East. Instead, Atlanta roared to life, passed the Mets during a late-season series at Truist Park and won the division for a fifth straight season, at 101-61. That earned the club a bye through the Wild Card Series. But then the Phillies, who finished 14 games behind the Braves in the standings, beat them in four games in the NLDS.

2021: Dodgers (Lost in NL Championship Series)
New champion: Braves
The 2021 Dodgers won 106 games and added the likes of Max Scherzer and Trea Turner to help their repeat efforts, but Los Angeles couldn't get by the Braves in the NLCS, losing in six games. The road wasn't made easy for them, though, as they avoided elimination four separate times in the playoffs before finally falling in their fifth chance.

2020: Nationals (Missed playoffs)
New champion: Dodgers
The 2020 club repeated the previous year’s 19-31 start. But while the ‘19 Nats had time to surge back into a postseason spot, the 60-game schedule gave their successors no such leeway -- even with an expanded 16-team playoff field. After the high of a seven-game World Series triumph over the Astros, the 2020 Nats never rose above the .500 mark or made a serious run at a playoff spot.

2019: Red Sox (Missed playoffs)
New champion: Nationals
The 2018 Red Sox could do no wrong, winning 108 games and then going 11-3 on their October championship run. The ‘19 club won only 84 games, finished 12 out of a playoff spot, then traded franchise player Mookie Betts to the Dodgers in the ensuing offseason.

2018: Astros (Lost in AL Championship Series)
New champion: Red Sox
Houston looked like a strong bet to end the streak, winning two more regular-season games in 2018 (103) than it did the year before, after adding a suddenly dominant Gerrit Cole to its rotation alongside Justin Verlander. It all came crashing down with a five-game ALCS loss to Boston.

2017: Cubs (Lost in NLCS)
New champion: Astros
When the 2016 Cubs broke their longtime championship drought with a team featuring a number of young stars, many were imagining the beginning of the next baseball dynasty. It didn’t quite work out that way. Chicago won 92 games and another division title the next year and advanced to the NLCS, but the Dodgers outscored them 28-8 in five games.

2016: Royals (Missed playoffs)
New champion: Cubs
After missing the postseason in 28 straight seasons, Kansas City’s rebuild finally bore fruit with back-to-back World Series trips, including a victory over the Mets in 2015. But about as quickly as those plucky Royals emerged, the run was over. The ‘16 team finished at .500, eight games out of another trip to October.

2015: Giants (Missed playoffs)
New champion: Royals
San Francisco’s even-odd pattern continued, following championships in 2010, ‘12 and ‘14, and postseason misses in ‘11 and ‘13. This Giants team won only four fewer games (84) than its ring-bearing predecessor but finished eight games behind the rival Dodgers for the NL West crown.

2014: Red Sox (Missed playoffs)
New champion: Giants
The 2013 club had gone from worst in the AL East (69-93) to first (97-65) on the strength of some savvy offseason moves. But Boston couldn’t recreate that magic, and it was right back to last place (71-91) the next year.

2013: Giants (Missed playoffs)
New champion: Red Sox
This was more or less the same team that won 94 games and found October magic in 2012, but this time, the mix didn’t quite work. After a 28-22 start, San Francisco went through a 28-50 swoon in the middle of the season, falling well out of the race.

2012: Cardinals (Lost in NLCS)
New champion: Giants
St. Louis benefited from the debut of the two-Wild Card system in 2012, grabbing that extra spot with 88 wins, beating the Braves in the first NL Wild Card Game and advancing to the NLCS. The Cardinals then took a 3-1 lead over the Giants before dropping three straight by a combined score of 20-1.

2011: Giants (Missed playoffs)
New champion: Cardinals
The 2010 Giants won the franchise’s first championship since moving to San Francisco. The followup act -- still led by Madison Bumgarner, Matt Cain and Tim Lincecum -- went 86-76 but finished four games out of a playoff spot.

2010: Yankees (Lost in ALCS)
New champion: Giants
The Yankees finished the 2000s on top, but little did anyone know they would not win another championship throughout the entirety of the 2010s. Their first team of the new decade went 95-67 but had no answer for Rangers sluggers Nelson Cruz and Josh Hamilton in the ALCS.

2009: Phillies (Lost in World Series)
New champion: Yankees
These Phillies are the most recent defending champion to even return to the World Series. Philly had no trouble getting past the Rockies and Dodgers for its second consecutive NL pennant but couldn’t capitalize on taking Game 1 of the Fall Classic in the Bronx.

2008: Red Sox (Lost in ALCS)
New champion: Phillies
Boston was about as good following its 2007 championship (95-67), but the upstart Rays made sure there wasn’t a repeat. Joe Maddon’s crew edged the Sox by two games for the AL East title, then knocked them off in a dramatic, seven-game ALCS.

2007: Cardinals (Missed playoffs)
New champion: Red Sox
The 2006 Cardinals had squeezed into the postseason with an 83-78 record, but the ‘07 club couldn’t reach that modest bar, going 78-84. Entering 2020, that remains St. Louis’ only sub-.500 season of this century.

2006: White Sox (Missed playoffs)
New champion: Cardinals
Ozzie Guillen’s bunch had another strong season, winning 90 games in 2006. Unfortunately for Chicago, that was only good for third in the AL Central that year behind the 96-win Twins and 95-win Tigers.

2005: Red Sox (Lost in AL Division Series)
New champion: White Sox
What can you possibly do for an encore after snapping arguably the most infamous championship drought in professional sports? There was no hangover for Boston, which went 95-67, but this time the White Sox were the drought-ending team of destiny, taking a three-game ALDS sweep.

2004: Marlins (Missed playoffs)
New champion: Red Sox
The Marlins jumped out to a 30-20 start and had a share of the NL East lead through the end of June. But the Braves ran away with the division after that point, and the Marlins (83-79) wound up nine games out of a Wild Card spot.

2003: Angels (Missed playoffs)
New champion: Marlins
The Halos jumped from 75 to 99 victories in 2002, fighting their way to the franchise’s first championship. Then they plummeted right back to 77 wins before reaching the postseason in five of the following six seasons.

2002: D-backs (Lost in NLDS)
New champion: Angels
Arizona actually improved by six wins in the season after winning the World Series, going 98-64 and winning the NL West again. But after beating the Cardinals in the 2001 NLDS, Arizona couldn’t repeat the feat, as St. Louis knocked around Randy Johnson in Game 1 and went on to a sweep.

2001: Yankees (Lost in World Series)
New champion: D-backs
New York won four World Series in five years from 1996-2000, going 12-1 in the Fall Classic in the last three seasons of that span. But the Yanks finally met their match in the 2001 D-backs, who got brilliant work from Randy Johnson and Curt Schilling, walking off on Luis Gonzalez’s single in Game 7 of the World Series.