Dodgers shortstop Corey Seager’s status in jeopardy for Game 1 as back soreness lingers

Held out of workouts for the third consecutive day because of an issue with his back, Dodgers shortstop Corey Seager may not be able to play Game 1 of the National League Championship Series, manager Dave Roberts acknowledged at a workout on Friday.

Roberts described the injury as a “muscular issue.” He insisted that he was “very optimistic” about Seager being in the lineup on Saturday at Dodger Stadium, but could not guarantee it.

“There’s always a possibility,” Roberts said. “But with the back injury, that kind of locked him up a little bit. But right now he’s getting treatment. Has gotten treatment the last couple days, and every day keeps getting considerably better.”

Seager did not appear in the clubhouse while it was open to reporters on Friday. Roberts indicated Seager injured his back while sliding into a base during Game 3 of the National League division series against Arizona. Seager posted a .467 on-base percentage in the series.

Seager missed nearly two weeks in September as he rested his sore right elbow. The inflammation in the joint may require offseason surgery. His elbow hurts each time he throws the baseball, Seager has said.

The Dodgers have tried to manage Seager’s between-game workload all season to keep him fresh for October. That same philosophy applies to this current situation, Roberts said.

“It’s just one of those things that we’ve just got to be mindful of,” Roberts said. “Want to keep him off the field. I think it will help the back, the elbow, the whole workload thing, which we’ve done all year. But we’re very optimistic he’ll be in there on Saturday.”

Hill, then Darvish, in rotation

The Dodgers opted not to deviate from their rotation alignment from the first round, when Rich Hill started Game 2 at Dodger Stadium and Yu Darvish started Game 3 on the road.

Hill posted a 2.77 earned-run average at home during the regular season; Darvish produced a 2.44 ERA on the road.

Alex Wood is scheduled to start Game 4 at Wrigley Field.

Short hops

Roberts described the team as “at the 5-yard line” in finalizing the 25-man roster, which is not due until Saturday. If the team alters the composition from the first round, left-handed reliever Luis Avilan could replace either right-handed reliever Pedro Baez or right-handed reliever Ross Stripling. Avilan was unavailable against Arizona as he recovered from a sore shoulder. … The Cubs have not announced a starter for Game 1, but manager Joe Maddon indicated Jon Lester is the likely choice for Game 2 on Sunday.

andy.mccullough@latimes.com

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