The New York Yankees will begin their Wild Card Series against the Boston Red Sox without Aaron Judge.

Judge was left off the roster because of a strained right calf that has kept him sidelined since mid-September. He had worked toward a return and participated in live batting practice, but New York ultimately decided he was not ready for the opening round.

The absence changes the Yankees’ lineup immediately. Judge is the centerpiece of the offense and one of baseball’s most dangerous power hitters when healthy. Without him, New York will need more production from the rest of the order and may have to manufacture runs differently.

The Yankees did receive some positive injury news elsewhere, with other veteran hitters available for the series. Still, there is no direct replacement for Judge’s combination of power, patience and presence in the middle of the lineup.

The timing is especially difficult because a short postseason series leaves little margin for error. A team can be eliminated before an injured star has enough time to recover.

For Boston, Judge’s absence changes the way pitchers can attack the Yankees. The Red Sox can be more aggressive in certain matchups without having to navigate around New York’s captain every time the heart of the order comes up.

The Yankees now face a straightforward challenge: survive the opening round without their biggest bat. If they advance, the conversation immediately becomes whether Judge can return later in October.