MIAMI -- Summer Camp workouts at the Marlins’ complex in Jupiter, Fla., got a little more lively on Saturday.

After missing the first week of camp, Jazz Chisholm made his first appearance, as the 22-year-old was assigned to train with the organization’s top prospects at the complexes at Roger Dean Chevrolet Stadium.

Ranked by MLB Pipeline as Miami’s No. 3 prospect, Chisholm is a high-energy shortstop prospect who made a strong impression with the big league staff in Spring Training.

Chisholm missed the first week of camp, and now he has two weeks to get ready for the regular season, which begins on July 24 at Philadelphia.

Even if he doesn’t make the Marlins’ 30-man Opening Day roster, the left-handed hitter has a chance to be in the big leagues at some point in 2020.

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“It’s good to have Jazz back,” Marlins manager Don Mattingly said during a Zoom call Saturday. “The good thing about Jupiter is there’s lots of reps, so there’s lots of at-bats there.”

Actually, on Saturday several of the top position player prospects, like outfielders JJ Bleday and Jerar Encarnacion, and infielder José Devers, worked out at Marlins Park, where the big league staff have been running practice. The players in Miami are the expected big leaguers.

“The guys in Jupiter are real guys,” Mattingly said. “These aren’t just guys you threw there so they could take BP.”

Chisholm is close to big league ready. He showed that in Spring Training, hitting .308 (4-for-13) with one home run, two stolen bases and three RBIs in nine Grapefruit League games.

The Marlins acquired Chisholm from the D-backs last July in exchange for right-hander Zac Gallen.

Chisholm spent 2019 at the Double-A level, combining to hit .220 with 21 home runs and 54 RBIs. After the trade, he had a slash line of .284/.383/.494 with three homers and 10 RBIs in 23 games.

“I think the real tragedy this year, and we don’t get to talk about it that much is, the Minor League guys and development, because there are no games,” Mattingly said. “That’s tough, especially for an organization like ours, where you’re starting to fill up your system.”

Prospects could play in 2020
Anyone on the 60-man player pool has a chance to be in the big leagues in 2020. Mattingly made that clear on Saturday.

“Anybody that’s on this 60 has a chance to contribute at the big league level,” Mattingly said. “Obviously, you make some different choices in there because you want guys to continue to play and things like that.”

Those on the 40-man roster, like Chisholm, have an advantage. But prospects like Bleday and right-hander Max Meyer, Miami's first-round Draft picks in 2019 and '20, respectively, could also crack into the big leagues in '20.

Right-handers Sixto Sánchez, Edward Cabrera and Jorge Guzman could also be called upon. According to MLB Pipeline, they are Miami’s Nos. 1, 5 and 19 rated prospects, respectively.

“[Jupiter] guys could get here quickly because of total necessity,” Mattingly said.

Ureña adjusting, adapting
Based on his track record and impressive Spring Training, José Ureña has cemented a starting spot. Where exactly he will pitch in the rotation has yet to be announced.

A reason he's improving, according to Mattingly, is he's using both sides of the plate better.

“The adjustments I made in Spring Training, I tried to put more attention on throwing to the outside corner for a righty and inside for a lefty," Ureña said on Saturday. "And throwing more four-seamers."

Ureña has primarily relied on a two-seam fastball, or sinker, which has a lot of movement and tends to run inside on right-handed hitters. His average velocity on the pitch in 2019 was 95.8 mph, per Statcast.

When the two-seamer gets away from him, Ureña tends to hit a lot of batters. The right-hander paced the National League in hitting batters in 2017 (14) and '18 (12).

In 2019, Ureña logged just 84 2/3 innings, missing several months due to a herniated disc. He hit two batters.

Now he is mixing in his four-seam fastball, which he uses to get the ball to the outside part of the plate to right-handers, and in on lefties.

“I think what we saw in Spring was a guy who was more willing to make some adjustments,” Mattingly said. “He used the four-seam. He used both sides of the plate. Hopefully, we’re able to carry that forward, using the four-seamer at times. The two-seam has obviously been his pitch.”

Sim-game starters
The Marlins will have another simulated scrimmage on Sunday, with Jordan Yamamoto and Elieser Hernandez each scheduled to pitch.