Boston Red Sox (7 percent World Series probability) Strength: That ridiculous offense.To say the Astros are a great hitting team would be an understatement. They’re not merely great by 2017 standards. They rank among the most explosive offensive teams in major league history. Only three teams since 1901 — Babe Ruth and Lou Gehrig’s 1927, 1930 and 1931 New York Yankees — had a better wRC+ than Houston did this season, which explains how they racked up nearly 900 runs and led the majors in offensive WAR by a mile. Led by MVP-candidate second baseman Jose Altuve and his .957 OPS, six Astros ranked among MLB’s top 37 hitters by WAR, with a seventh (first baseman Yulieski Gurriel) clocking in at No. 48. And the damage they did to opposing pitchers could have been even greater had shortstop Carlos Correa not missed 42 games at midseason: With Correa in the lineup, the Astros scored 22 percent more runs per game than they did without him. (He’ll be at full strength for the playoffs — be afraid, AL pitchers.)Weakness: Fielding … and the bullpen.The Astros bolstered their starting rotation with the last-minute addition of erstwhile Tigers ace Justin Verlander, who has been extra sharp since joining Houston. But there are still some holes in the team’s run-prevention corps: Aside from Ken Giles and goose-egg darling Chris Devenski, the Astros have few impact arms waiting in the bullpen. And on defense, they’ve been the eleventh-worst fielding team in MLB according to The Baseball Gauge, with zero position players who could be fairly classified as stellar with the glove. Houston’s starters aren’t the liability they’re sometimes made out to be, and this lineup might score so many runs that it won’t matter anyway, but the Astros might have reason to worry in tight postseason contests. Houston Astros (16 percent World Series probability) The MLB playoffs are finally upon us, and to help set the scene, we’re previewing the division-series field — sorry, Twins — for each league. For every team, we picked out their most important strength, plus the one weakness that might trip them up en route to the World Series. Now all that’s left is to watch it all play out in what should be one of the most exciting postseasons ever. First up is the American League. Cleveland Indians(25 percent World Series probability) Strength: Pitching.According to The Baseball Gauge’s wins above replacement meta-metric,1Which averages aspects of the versions of the WAR stat found at Baseball-Reference.com and FanGraphs, in addition to Baseball Gauge’s own WAR metric. Specifically, for this article I set the meta-metric to average together every option equally in each category, with no regression for fielding metrics and the positional adjustment not included in offensive and defensive WAR. no team in baseball got more value out of its rotation or its bullpen this season than the Indians, who boast two of the AL’s top 10 starters (Corey Kluber and Carlos Carrasco) plus its second-best reliever (Andrew Miller). That trio helped Cleveland’s staff lead the majors in strikeout rate, walk rate and home run rate,2The fielding independent pitching triple crown! despite having to face those pesky designated hitters.3Who, granted, aren’t quite as pesky as they used to be. And don’t sleep on the back end of this rotation, either — Mike Clevinger and Trevor Bauer had strong seasons as well — or a defense that ranked sixth best in baseball. If pitching and defense truly win championships, nobody is better equipped for October than the Tribe.Weakness: Offensive star power.If the Indians do have a weakness — and admittedly it’s something of a stretch to say this about a team that cleared 800 runs scored — it’s their lack of truly dominant bats in the middle of the batting order. Cleveland is a good hitting team — it ranked third in weighted runs created plus (wRC+, a measure of offensive production that’s adjusted for park and league effects) this season — but third baseman Jose Ramirez was the team’s only hitter to rank among the top 25 in offensive WAR. (DH Edwin Encarnacion and shortstop Francisco Lindor ranked 35th and 43rd, respectively.) The midseason acquisition of solid-hitting right fielder Jay Bruce helped in this department, and the Tribe had an MLB-best .843 on-base plus slugging in September, led by a surging Encarnacion. But if we look at the whole season, Houston had four of the top 25 hitters by WAR (more on that later) and even Arizona had two. Again, though, that might be nitpicking. This team is really, really good. Strength: Underlying talent.Even by the standards of baseball’s most successful franchise, the Yankees had a fine year in 2017, winning 91 games and dragging the AL East race down to the season’s final weekend. (The Red Sox also helped in that department.) And there’s a strong case to be made that the pinstripers are much better than their record indicates. New York had an 18-26 record in games decided by 1 run, one of the worst marks in baseball. Yet according to context-neutral stats such as WAR, the Yankees also had one of MLB’s best bullpens — not what you would expect if a team was truly shaky in close games. Between bad luck in those kinds of contests and slightly unlucky sequencing,4Meaning the difference between a team’s actual run differential and what we’d expect based on its underlying stats. This can be attributed to how much a team sequences its hits and walks, concentrating them within innings (which helps scoring), or scattering them across innings (resulting in fewer runs). Much of that is a function of luck, but it can have a profound effect on a team’s record. the Yankees won 11 fewer games than their stats would have predicted, the biggest shortfall in MLB. New York’s 102 wins “on paper” is a much better descriptor of how good it is than its 91 wins in the standings — and that makes the Yankees one of the postseason’s most sneaky-dangerous teams, especially now that they’re through into the division series.Weakness: Offensive inconsistency.Just like its best player, Aaron Judge, this Yankee offense tends to run very hot or very cold. While New York’s runs allowed per game remained pretty constant throughout the year, its scoring rate bounced around between incredible (with particular spikes in early May, June and most of September) and mediocre (see late May, as well as practically all of July and August), resulting in the fifth-largest standard deviation in runs per game of any team in baseball. Judge himself was responsible for this to a large degree, hitting like a runaway MVP in the first half, then cratering for a month and a half before recovering in September. If Judge and company go cold again — and New York’s pitchers can’t offset the drop after a taxing wild-card game — the Yankees’ playoff run could end quickly. New York Yankees (8 percent World Series probability) Strength: Preventing runs.The Red Sox had the second-best earned run average (adjusted for park effects) in the AL during the regular season, and there’s a lot credit to go around for that. Recent hiccups notwithstanding, Boston’s starting rotation ranked fourth in MLB by WAR, led not only by Chris Sale’s historically dominant numbers but also by under-the-radar seasons from Drew Pomeranz and Eduardo Rodriguez. The Red Sox bullpen, headlined by AL-leading closer Craig Kimbrel, finished third-best in WAR and often outpitched its overall numbers in important moments. Defensively, Boston ranked fourth in WAR, anchored by Sandy Leon behind the plate and the strong glovework of Mookie Betts and Andrew Benintendi in the outfield. And Boston might be even tougher to score against in October, with lefty David Price coming back from injury to play what appears to be an Andrew Miller-esque role out of the Sox bullpen.Weakness: Power hitting.Somehow, a team that put almost 900 runs on the board a year ago registered as barely above-average this season, despite the rising tide of baseball offense. Why? Many of Boston’s scoring issues can be traced back to a mysterious power outage that saw them rank third-to-last in isolated slugging (ISO) during the regular season. Among Boston’s nine 2017 regulars5Qualified with at least 200 plate appearances. who were also with the club last season, eight saw their ISO drop, and by an average of 37 points. Compounded by the retirement of David Ortiz, who departed with one of the greatest career-ending seasons ever, the Red Sox’s slugging woes left them ranked 20th in offensive WAR a year after they led all of baseball in the metric. (Aging vets like Dustin Pedroia and Hanley Ramirez failed to pick up Ortiz’s slack, and almost all of Boston’s young hitters fell off their 2016 form.) After another month of poor hitting, don’t be surprised if this offense is a major source of anxiety for Boston in the postseason.Check out our latest MLB predictions.