How The Cubs Won The NL Wild-Card Game

The Pirates have had the bad fortune of running into dominant starters for their wild-card game matchups in recent years: Last season, they were shut out by the Giants’ Madison Bumgarner, and this year they’re having trouble hitting Jake Arrieta. How tough were those aces to score against? Bill James, the father of sabermetrics, keeps a running ranking of the best starting pitchers in baseball at any given moment (his system is similar in some ways to the Elo ratings we often use), and James’s system had Bumgarner ranked sixth in the league when he tore through Pittsburgh’s lineup. Bumgarner would eventually rise to second after a brilliant playoff run. Arrieta is in between the two Bumgarners: He ranks fourth. Facing starters of that caliber in a one-and-done situation in back-to-back years makes it pretty tough to advance past the wild-card round. It’s probably no coincidence that in 2013, the one year Pittsburgh did make it past the play-in game, they drew 59th-ranked Johnny Cueto instead.

With a 4-0 lead, the Cubs are well-positioned to pull out the win in this wild-card game. FanGraphs win probability has the Cubs as more than a 90 percent favorite to win at the moment. But even that may be conservative: The Cubs boast one of the best bullpens in the majors (fourth by fWAR), and they will use as many relievers as necessary to get the win in this do-or-die game. It’s likely that the 90 percent win probability we currently assign them is, if anything, conservative. It should be more like 95 percent.