1 DOES MOMENTUM MATTER?
Just as baseball fans were getting used to a world in which the Dodgers were the best team of all time and the Indians were suffering from a Game 7 letdown, everything changed: Los Angeles couldn't win (it lost 16 of 17, including 11 straight), and Cleveland couldn't lose (an AL-record 22 victories in a row, and a 30--4 record over the last five weeks). Surely this means that Cody Bellinger (left) and the Dodgers are likely to bow out in the NLDS while the Indians cruise into the World Series? Fortunately for L.A., a study by SI's Jay Jaffe found that momentum doesn't matter going into the playoffs. If a team goes 25--5 in the final month, it has no greater chance of piling up postseason wins than a team that finished with the same number of overall victories despite a late-season tailspin. In other words, the (at week's end) 98-win Indians and the 99-win Dodgers should have similar chances to keep playing deep into October.
2 CAN STARS GET HEALTHY?
It's unlikely that any team can match the dramatic success of last year's Cubs, who quietly rehabbed Kyle Schwarber—six months removed from surgery to repair a torn left ACL and LCL—and added him to their World Series roster as a DH. This year's biggest shelved star, Nationals rightfielder Bryce Harper, plans to return from a left-knee injury in time for the postseason, which could make Washington the NL favorites. Outfielder Michael Brantley, who has missed six weeks with a right-ankle injury, could do the same for the Indians in the AL, but he suffered a setback last week. Red Sox starter David Price has returned from left-elbow pain and could be an x-factor as a multi-inning reliever, but given his shaky work this season, don't expect him to become Boston's answer to Andrew Miller. And Chicago will try to re-create some of last year's Schwarber magic: No. 2 starter Jake Arrieta (left) returned last week from a right-hamstring strain and allowed only one run in five innings.
3 WHO'S DUE FOR A BREAKOUT... ?
Predicting playoff performance is almost impossible; anything can happen over five (or 12 or 17) games. That said, luck—good or bad—is bound to change at some point, and the postseason is as good a time as any. Curtis Granderson, for example, has hit .139 since he joined the Dodgers from the Mets in mid-August, but a closer look at the numbers reveals that he's been unsustainably unfortunate: He's hitting the ball harder than ever, yet nearly 90% of the time that he puts a pitch in play, defenses turn it into an out. If Granderson keeps doing what he's doing, he'll get better results sooner or later—for Los Angeles's sake, the sooner the better. Astros outfielder Carlos Beltrán (left) is experiencing a similar disparity in process and result. And in alarming news for his future opponents, Red Sox ace Chris Sale, of the 2.75 ERA, has also been unlucky; his strikeout rate, walk rate and home run rate indicate that his ERA should actually be closer to 2.22.
4 ... AND WHO'S DUE FOR A SLUMP?
Dodgers outfielder Chris Taylor may be facing a reckoning. The formerly middling prospect broke out this year with an OPS of .867, but some of that has come on an unusually good batting average on balls in play (.362), which is likely to regress. In fact, it's already begun: After hitting .305 with a .530 slugging percentage through August, Taylor is so far hitting .202 and slugging .348 in September. Meanwhile, lefthander Gio González (left) has had a terrific year—his 2.68 ERA is tied for third best in the NL—but the same peripheral numbers that portend a good future for Chris Sale suggest that there could be trouble ahead for the Nationals' No. 3 starter. González is striking out, walking and allowing home runs to batters roughly as often as he did last year, when his ERA was 4.57.
5 IS IT ANOTHER YEAR OF THE BULLPEN?
Terry Francona set the tone early last October when he summoned lefty Andrew Miller (left) in the fifth inning of Game 1 of the ALDS to protect the Indians' one-run lead. Relievers ended up throwing 43% of the innings in last year's postseason, the most in the LCS era. Their 9.5 strikeouts per nine innings were second only to the 9.6 in 2015. Still, statistically inclined observers, who have long called for more creative bullpen usage, shouldn't get too excited: Those numbers were skewed by Cleveland's deep run and, more important, this year's playoffs feature significantly stronger rotations. A healthy Carlos Carrasco joins Corey Kluber for the Indians; the Dodgers supplemented Clayton Kershaw with Yu Darvish; the Nationals can follow Max Scherzer with a healthy Stephen Strasburg. You can expect to see fewer firemen because the starters will allow fewer fires.
6 WILL THERE BE SIGN-STEALING DRAMA?
The Yankees--Red Sox rivalry, dormant in recent years as the two teams' cycles of success fell out of sync, got a jolt this September. New York accused Boston of stealing signs using an Apple Watch—or maybe it was a FitBit—and Boston counter-accused New York of using a YES Network camera to do the same. (MLB fined the Red Sox an undisclosed amount for using an electronic device in the dugout; the Yankees were fined a lesser undisclosed amount for a past infraction involving a dugout phone.) The division front-runners would not meet until the ALCS, but sign-stealing story lines will pervade the postseason no matter what the matchup is. With monitors now behind every dugout as part of the replay system, nearly every team is taking advantage of the possibilities, if usually without smart watches. Expect many catcher-pitcher conferences on the mound this October to change up the signs.