LOS ANGELES -- Manager Dave Roberts’ Zoom call on Saturday repeatedly landed on the “D” word, and it wasn’t Dodgers.

“Different,” Roberts kept saying when asked for early returns on the Summer Camp that officially started Friday.

In truth, the Dodgers and other clubs started Summer Camp early, which is why starting pitchers like Clayton Kershaw and Alex Wood are already throwing four or five innings in simulated games.

Roberts sounded comfortable with the physical condition and focus of the players currently working out at Dodger Stadium. But he conceded that the biggest concern he has in the three-week leadup to Opening Day is not knowing which players won’t be available because of COVID-19.

“The biggest concern is you just don’t know who the 30 [players on the Opening Day roster] will be in the sense that it just won’t be a typical situation when you’re talking about physical health, an arm or hamstring or oblique,” he said. “Now, we just don’t know and can’t predict. We have guys we think will break camp with us, but now there’s another variable that we just can’t account for. That uncertainty is weighing on me and us the most.”

That has required, Roberts said, to envision the equivalent of multiple depth charts to cover the absence of every player and the resulting domino effect.

“Every organization has to go through that,” he said. “The ramp-up, I’m very confident. Starting pitchers, position players getting their at-bats, guys in the ‘pen will be ready to go. But you just don’t know when somebody will be affected and it can change the landscape. That’s what we all have to deal with.”

That said, Roberts remains the eternal optimist.

“I feel we’re going to get through it,” he said. “I don’t think our guys should think otherwise. To entertain that we can’t start or not going to finish, I don’t think that’s helpful. We’re ... being responsible, but ready to play baseball.”

• Roberts repeated earlier comments about opening the season with a five-man starting rotation and using a committee for the designated hitter instead of one or two primary DHs.

When Spring Training was paused, the five-man rotation was Kershaw, Walker Buehler, David Price, Julio Urias and Wood. With Price electing not to play this season, swingman Ross Stripling is the most likely replacement.

In 10 games last year Roberts used six DHs, led by Justin Turner (three times). Also in the role last year were Matt Beaty, David Freese, Joc Pederson, Will Smith and A.J. Pollock.

• Buehler, calling himself a traditionally “slow starter,” said he plans another bullpen session or two before facing hitters for the first time and wouldn’t guess “what it’s going to look like” by his first regular-season start.

He added that, with a maximum of three exhibition games allowed to each club, he isn’t concerned ramping up from facing Dodgers hitters to games that count without the usual five or six spring starts against opponents.

“I’ll be facing our hitters. With how talented we are, nothing against any other team, but facing some of our guys is as good as it gets,” he said.

• Former Marlins closer AJ Ramos, invited on a Minor League contract, is expected to report Saturday or Sunday, Roberts said.

• Roberts said the club is using USC as its alternative training site with fewer than 10 players there currently, mostly pitchers and catchers. Minor League staffers Travis Barbary, Don Alexander and Clayton McCullough are overseeing the workouts. That operation is expected to relocate to the club’s California League affiliate, Rancho Cucamonga, when the semester starts at USC.