The Cubs had to fight for their right to the party they threw after Saturday’s NLCS Game 6. Although baseball’s best team hasn’t faced an elimination game, both of its playoff opponents have pushed it to the point that Chicago’s burned-before fans have indulged in defeatist fantasies (which, admittedly, doesn’t take too much prompting). The Indians, meanwhile, trailed for a total of only eight innings in the eight games it took them to advance to the World Series, and all but one of those innings came in their lone loss, ALCS Game 4.

The story of the Indians’ October run has been the back of their bullpen, particularly Cody Allen and ALCS MVP Andrew Miller, who are tied for third among all players this postseason in championship win probability added. In 12 combined outings, Miller and Allen have thrown 19 1/3 scoreless innings, whiffing 46 percent of the batters they’ve faced. That number, 46, is significant for another reason: It’s also the percentage of Indians postseason innings thrown by relievers, which represents a marked increase from their 35 percent tally during the regular season. With Miller and Allen tag-teaming to throw more than a quarter of the Indians’ playoff innings — and potential AL Cy Young Award winner Corey Kluber contributing more than a quarter on his own — the Indians have looked almost unbeatable, even with the injured Carlos Carrasco and Danny Salazar absent from their rotation.

Related The Indians Are Reshaping How We Think About Relievers

Fortunately for the Cubs, seven games can be deceiving. In October 2014, shortly after the Royals had gone 8–0 en route to a pennant, Sam Miller and I spoke (and Sam wrote) about the two Royals teams: the one when they were leading, and the one when they were trailing. When they were winning, the Royals could deploy their shutdown defense, inserting Jarrod Dyson to complete their ultimate outfield and assigning their late innings to the trio of Kelvin Herrera, Wade Davis, and Greg Holland, all of whom had pitched in succession in seven of those eight wins. Those Royals also appeared to be unbeatable. In the World Series, though, the victorious Giants took early leads against Royals pitching, preventing Kansas City from using their summons. Even though the series went seven, Kansas City called on Herrera, Davis, and Holland in the same game only three times. Once they were losing, the Royals were just another pretty good team.

In that sense, this year’s Indians are a lot like those two-faced Royals, only even more extreme. The table below shows the Indians’ winning percentages when ahead or behind after each inning in 2016, including postseason play. The “difference” columns compare the Indians’ winning percentages to those of the league as a whole. The higher the number, the bigger the margin by which the Indians have been better than the MLB baseline.

The Indians are really, really good when they get a lead. When they’ve gone ahead in the first inning, they’ve won at the pace of a 136-win team, and they’ve only improved the later their leads have lasted. The Indians aren’t bad when they’re behind, either; they’ve been better than the typical team when trailing after every inning except the fifth. In every case, though, the difference between the Indians’ winning percentage and the league’s is smaller when the Indians are losing. Relative to the rest of the league, the Indians have been much better at holding leads than they have at regaining them.

Keep in mind that those results include the period before the Indians traded for Miller at the end of July, when the Indians’ bullpen was good but not noteworthy. Now they play an even better brand of prevent defense. With Miller on their roster in the second half of the season — and Terry Francona making the most of his presence — the team’s pen posted baseball’s best park-adjusted FIP and xFIP and finished a close second to the Orioles’ relievers in win probability added. Fall behind the Indians in the playoffs and you’re very likely to lose.

Related The Game That Made Closers Cool

As amazing as Miller and Allen are, though, they can’t score runs. Nor can they prevent an opponent from taking a lead if the pitchers who’ve preceded them have left the Indians at a deficit. The best they can do if the Indians are already trailing is to keep the score close, and that’s not so scary. Get ahead in the early innings, and you all but neutralize Miller and Allen, exposing the Indians as a vulnerable team.

It’s not as if the Indians’ opponents haven’t already been trying to get ahead early. They just haven’t had any success. Cleveland’s postseason starters have allowed 1.86 runs per nine innings. Starters facing the Indians, meanwhile, have allowed 5.14 runs per nine innings. That massive disparity has translated to a lot of early leads — which, with the Indians’ pen, usually turn into late leads and, a little later, Cleveland victories. Thus far, the Indians’ opponents have found themselves in the unenviable position of needing to hit Miller and Allen to win. That’s not an impossible task — as distant as the memories might seem, the two have allowed runs on occasion — but it’s a low-percentage proposition.

The good news for Cubs fans is that the big gap in starter success that’s propelled Cleveland to this point is unlikely to persist. A few weeks ago, the Indians’ short-handed rotation seemed so weak that some observers declared them done. Writing them off was an overreaction, but despite Josh Tomlin’s tinkering, it would also be a mistake to see him, Ryan Merritt, and a drone-damaged Trevor Bauer as anything but the underbelly of the team. The Indians will have a harder time scoring off of Jon Lester, Kyle Hendricks, Jake Arrieta, and John Lackey — not to mention the Cubs’ incredible defense — than they did against Boston or Toronto, and Chicago’s offense is as strong as any team’s. The Cubs will have the superior starter in any game Kluber doesn’t start, and sooner or later, that advantage is bound to turn into leads that will rob the Indians of their late-inning assets.

It’s no coincidence that the only Indians playoff games in which Miller and Allen haven’t pitched were a Kluber gem and the one Cleveland lost. In the latter game, the Blue Jays took the lead in the third and never lost it. There’s an old saying about aces: You gotta get ’em early. With aces, it mostly doesn’t make sense. With the Indians, it applies perfectly.