Jorge Alfaro gave the Marlins a not-so-subtle reminder of how hard he can hit a baseball

Let’s start this with the appropriate disclaimer: It was batting practice, first underhanded tosses from hitting coach Eric Duncan maybe 25 feet away, then from a machine on the mound and then two live at-bats against relief pitchers Brandon Kintzler and Brad Boxberger.

But that doesn’t detract from one of the notable observations from the Miami Marlins’ third summer camp practice on Sunday, one that was seen at times last season.

Catcher Jorge Alfaro can do some serious damage when he hits a baseball.

“Just excited to get back out there,” Alfaro said.

Virtually every swing from him on Sunday produced the same result: A loud crack of the bat and a hard hit baseball, generally finding its way over the fence.

He hit AutoNation Alley in left-center field a couple times. A few were deposited into the old site of the Clevelander in left field (which has been turned into a makeshift workout room). A few more landed in the grass.

He turned on the second pitch he saw against Kintzer and sent it to the wall in right-center field.

He looked like the Jorge Alfaro the Marlins will want to see this season, the one who in 2019 hit 18 home runs and had a 44.8 percent hard-hit rate — defined by Statcast as a ball with an exit velocity of at least 95 mph.

The part they don’t want to see: The 38.4-percent swing-and-miss rate, the 48-percent chase rate (a career high) and the 33.1-percent strikeout rate.

Alfaro said he has been working with bench coach James Rowson to improve the offensive side of his game.

Health-wise, Alfaro said he is good to go after dealing with an oblique injury when spring training originally was halted on March 12.

More observations

▪ Pablo Lopez impressed most on the pitching side of live batting practice. His command was solid over his four innings of work, getting the array of batters he faced to swing and miss on pitches low and outside of the zone. He also struck out Corey Dickerson twice in three plate appearances (Dickerson, it’s worth noting, did make some nice contact in his final AB against Lopez).

▪ The others pitchers who took part in live batting practice on Sunday: Jose Urena (three innings) and relievers Kintzler, Boxberger and Sterling Sharp (one inning each). Urena was hit hard during his first inning against Dickerson and Sean Rodriguez, but settled down after that.

▪ First base prospect Lewin Diaz showed off his power during the live batting practice session, too, blasting a no-doubter off Boxberger to right-center field.

▪ After three days of practice and media viewing of five of the six sessions (we didn’t see the early Saturday session because of a team meeting taking place in the stands between the morning and afternoon practices), the Miami Herald saw all but three of the 42 players who were anticipated to report to Marlins Park for practice.

The three: shortstop prospect Jazz Chisholm and outfielders Lewis Brinson and Matt Joyce.

The Marlins also have 18 players who will primarily be working at the team’s spring training complex at Jupiter’s Roger Dean Chevrolet Stadium.

Marlins president of baseball operations Michael Hill announced Saturday that the team had four players from their 60-man roster pool test positive for COVID-19, one during Wednesday’s intake screening and three in the couple weeks prior who have been in self quarantine. The team has not identified the four players because the players did not give the team permission to do so.

▪ According to local radio host Craig Mish, the Marlins are reportedly opening the 60-game 2020 season on the road against the Philadelphia Phillies on July 24. The full schedule is expected to be released on Monday. Miami was originally supposed to face Philadelphia on Opening Day but at Marlins Park.

▪ A programming note: Monday’s practice is not open for media viewing. There will still be interviews with players and manager Don Mattingly via Zoom.