MIAMI -- When MLB shut down on March 12 due to the coronavirus outbreak, Sandy Alcantara was projected to be the Marlins' Opening Day starter.

Now that Summer Camp is ramping up, Alcantara was the first Miami starter to face hitters in live batting practice Saturday at Marlins Park.

"I'm ready," Alcantara said during a Zoom call. "I didn't stop working hard. For me, if the opener was tomorrow, I'm ready to go."

Opening Day will be either July 23 or 24, and Alcantara is the front-runner to get the nod on Day 1. In his tuneup on Saturday, the 24-year-old tossed five innings of simulated work, facing hitters in a controlled setting.

Alcantara and Caleb Smith were the two projected starters to face batters during the afternoon workout.

An All-Star in 2019, Alcantara logged 197 1/3 innings with a 3.88 ERA in 32 starts.

Even though the Marlins finished 57-105 in 2019, the youthful club is highly motivated to make an impact in the 60-game season.

"We are going to surprise a lot of people this year," Alcantara said. "It's a 60-game season. Everybody is going to see what we've got."

Building up the starters
Getting the Marlins starters built up isn't expected to be much of an issue, manager Don Mattingly said.

Most of the starters were built up to throw at least five innings late in Spring Training, and collectively, they kept throwing during the three-month shutdown.

Now less than three weeks to Opening Day, the Marlins are moving quickly into game-like situations.

"Everybody is kind of doing the same thing," Mattingly said. "Everybody is trying to figure out what's the best way to get your guys ready for baseball, as soon as possible.

"In our minds, that's trying to get them in game situations as much as possible. ... Get them at-bats, and then work our way into some sim games. Our pitchers have been working. Our guys have been built up pretty good. They were up to like five innings."

Easy as riding a bike
First baseman Jesús Aguilar arrived in camp Saturday, a day later than the rest of his teammates. That's because he was still awaiting his COVID-19 test results.

Aguilar said he stayed in shape during the shutdown by riding a bicycle.

"I tried to keep my body in shape while waiting for what was going to happen," he said. "I bought a bike. I've been riding for two months. That kept me in shape."

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Beyond the 60
The Marlins have one of the deepest farm systems in the Majors. Ideally, they'd like to avoid having to tap too deeply into it this year. But just in case, there is another wave of prospects who are on call, should their services be needed.

On Saturday, the Marlins announced that four unidentified players from their 60-man pool tested positive for COVID-19. One result was part of the intake screening process performed this week as players were reporting to Summer Camp.

Additionally, three others tested positive within the past two weeks and are currently in quarantine.

President of baseball operations Michael Hill explained the process if the Marlins were to need more reserves to fill out the 60-player pool.

"The process in putting the 60 together was very involved," Hill said. "There was a much larger pool for consideration. So those additional players who were in consideration for the ultimate 60 are that next wave."

At least a dozen of the Marlins' top prospects who are part of the 60-player pool are currently working out at Roger Dean Chevrolet Stadium in Jupiter, Fla.

Some of the prospects who are not on the 60-man pool but would be given consideration to be added, if needed, are infielder Jose Devers, outfielders Kameron Misner, Connor Scott and Peyton Burdick.

For any of them to be added to the 60-player pool, a player currently on the list must be added to the COVID-19 list or the injured list.

"On return, once healthy and cleared, then [the returning to action player] goes back on your 60-man player pool, and you have to remove someone to get back to 60," Hill said.

Monte, Miggy homer
Outfield prospect Monte Harrison is getting a second chance to make the Opening Day roster. In late March, Harrison was optioned to Triple-A Wichita shortly before rosters were frozen.

Now, Harrison is part of the player pool, and on Saturday he faced live pitching. Harrison belted a long home run off Smith.

Shortstop Miguel Rojas also connected on a home run off Smith.