Jake Arrieta last pitched Monday, so he’d be on full rest to start Game 1 of the NLCS on Saturday, but instead the Cubs have decided to start Jon Lester in the series opener against the Mets/Dodgers winner.
Lester also started Game 1 of the NLDS versus the Cardinals, but that’s because Arrieta was required for the Wild Card game against the Pirates. This time around the Cubs are simply choosing Lester over Arrieta for Game 1.
Lester certainly has far more playoff experience, logging 91 career postseason innings with a 2.66 ERA thanks to his time with the Red Sox. He allowed three runs over 7.1 innings in his lone NLDS start versus the Cardinals. Starting him in Game 1 of a playoff series was exactly what the Cubs had in mind when they signed Lester to a six-year, $155 million contract, but that was before Arrieta had a Cy Young-caliber season that includes one of the most dominant second halves in MLB history.
Arrieta was brilliant in the Wild Card game, shutting out the Pirates, but struggled somewhat in his lone NLDS start by allowing four runs in 5.2 innings. And perhaps the Cubs feel that, if necessary, Lester is more capable of pitching on short rest later in the series.