Like the Chicago Cubs going into last season, the Houston Astros enter the 2018 season as the favorites to win the World Series and become the first team to repeat since the 1998-2000 Yankees. But as we talked about in this space last year, there's a lot that can go wrong, which is why, over the past 40 years, only four World Series championships were earned by the reigning champ (the others were the 1993 Blue Jays and 1978 Yankees).
The ZiPS projections give the Astros a 14.4 percent chance of winning the World Series. As preseason projections go, it's hard to start with a probability much better than that given how MLB's postseason is structured and just how the game of baseball works. A team that enters four consecutive seasons with a 14.4 percent shot at winning the World Series is still more likely than not (54 percent) to get completely shut out of the championship.
Houston looked like a juggernaut on the way to 101 wins in 2017, never relinquishing the division lead after April 12th. Even a midseason spell during which pretty much every starting pitcher was injured -- the Astros ended up with zero ERA crown qualifiers -- wasn't enough to ever reduce the team's AL West cushion to 10 games.
But when any team wins 101 games, it's likely that a lot more went right than wrong. More 101-game winners are lucky 95-win teams rather than unlucky 107-win ones. And right now, ZiPS projects six other teams to have at least a 5 percent chance of winning the World Series. The computer projects roughly a 63 percent chance that the World Series winner in 2018 is one of these six teams, so it's more likely than not that one of them will be this year's baseball regicide.