CINCINNATI -- Ahead of Sunday’s 4 p.m. ET deadline, the Reds revealed a player pool of 57 that will be on their summer camp roster when the 2020 preseason resumes this week. With a limit at 60 players, there are three spots open.

“That doesn’t mean we can’t add players,” Reds general manager Nick Krall said.

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The Reds will report to camp on Wednesday, with their first official workouts anticipated to begin on Friday. MLB expects the regular season to start on July 23 or 24.

Most of Cincinnati’s 40-man roster will be among the 35 slated to train at Great American Ball Park. But there are some notable exceptions. Outfielders Aristides Aquino, Scott Schebler and Travis Jankowski will not train at GABP, but instead will be part of a 22-player group that will train during the preseason and season at Prasco Park in suburban Mason, Ohio.

Also included in the group slated to play in Mason are several of MLB Pipeline’s Top 30 Reds prospects -- left-handed pitcher Nick Lodolo (No. 1), catcher Tyler Stephenson (No. 3), infielder Jonathan India (No. 4) and shortstop Jose Garcia (No. 5).

Everybody on the summer camp roster is viewed as competing for a spot on the 30-man Opening Day roster or as someone who could contribute later in the regular season. That includes the players working out in Mason.

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“We tried to balance what we could from a working group standpoint. We have more pitchers coming to Great American Ball Park out of the chute than we do going to Prasco. We also have more catchers,” Krall said. “The rosters were broken up for one, from a social distancing standpoint as we begin, and two, to be able to maximize the amount of work in the work groups that guys can do.”

Prospects on the 60-man player pool will only gain service time if they are added to the active roster.

There are four players who were at Spring Training in Goodyear, Ariz., who won’t be part of the 60-man player pool, most notably Derek Dietrich, who was signed to a Minor League deal in February. Krall noted that Dietrich remains under contract and with the organization.

“That doesn’t mean we can’t bring him in at a later date,” Krall said. “We wanted to leave some roster flexibility.”

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Infielder Blake Trahan, catcher Chris Okey and pitcher Vladimir Gutierrez were also left off. Gutierrez was given an 80-game suspension by MLB on Sunday for testing positive for a performance-enhancing drug. Trahan notified the team that he was retiring.

The Reds placed more emphasis on adding players who could be big league ready this season. For example, 2020 first-round Draft pick Austin Hendrick, who just graduated high school, was not considered. But No. 2 prospect and pitcher Hunter Greene was not ruled out. Greene, the No. 2 overall pick in '17, last pitched for Class A Dayton in ’18.

“Hunter is coming back from Tommy John [surgery] and is pretty much finished with his rehab and building up,” Krall said. “He’s a guy who we’re trying to figure out how to maximize this year for him. We want to figure out how we’re going to progress him forward. He wasn’t a consideration now, but we have three spots open. We can always add him at a later date if and when someone is ready to be put on the 60-man roster.”

Great American Ball Park (35)

Pitchers (19): Trevor Bauer, Matt Bowman, Luis Castillo, Anthony DeSclafani, Amir Garrett, Sonny Gray, Raisel Iglesias, Nate Jones, Joel Kuhnel, Michael Lorenzen, Tyler Mahle, Wade Miley, Cody Reed, Sal Romano, Justin Shafer, Lucas Sims, Robert Stephenson, Pedro Strop, Tyler Thornberg

Catchers (3): Tucker Barnhart, Curt Casali, Kyle Farmer

Infielders (7): Alex Blandino, Matt Davidson, Freddy Galvis, Mike Moustakas, Eugenio Suárez, Josh VanMeter, Joey Votto

Outfielders (6): Shogo Akiyama, Nick Castellanos, Phillip Ervin, Mark Payton, Nick Senzel, Jesse Winker

Prasco Park (22)

Pitchers (11): R.J. Alaniz, Tejay Antone, Jesse Biddle, David Carpenter, José De León, Ryan Hendrix, Nick Lodolo, Alex Powers, Brooks Raley, Tony Santillan, Josh D. Smith

Catchers (2): Francisco Peña, Tyler Stephenson

Infielders (4): Christian Colón, Jose Garcia, Jonathan India, Alfredo Rodriguez

Outfielders (5): Aristides Aquino, Stuart Fairchild, Travis Jankowski, Boog Powell, Scott Schebler

Assuming that everybody remains healthy, the Reds' likely rotation will be comprised of Castillo, Gray, Bauer, DeSclafani and Miley, but the order hasn’t yet been revealed. It’s also not clear yet if manager David Bell and pitching coach Derek Johnson could try a six-man rotation or some other unique plan.

“Once we evaluate where they are, it’s a lot easier to make those decisions going forward,” Krall said. “I think we’re still working through that process of where guys are. If somebody is behind, that might make a different decision than for someone who is ready to go.”

The outfield remains a murky situation with Akiyama, Senzel, Castellanos, Winker, Aquino and Ervin. Some of Bell’s logjam will be lifted with the designated hitter being an option -- possibly for Castellanos, Winker or Aquino.

Payton is a Rule 5 Draft player who must remain on the roster for the season or be offered back to his former club.

According to MLB's Operating Manual, all players on a 40-man roster “that the Club anticipates participating” during the season will be part of the player pool, while the rest will be made up of non-40-man roster players under contract. Any 40-man-roster players who are not included in a player pool (for example, maybe a prospect who isn’t deemed ready for the Majors) will still be paid during the season.

No team will be allowed to exceed the limit of 60 players in its player pool at any time during Spring Training 2.0 or the regular season.

Several players have already arrived in Cincinnati to be tested for the COVID-19 virus and must isolate for two days before coming to the ballpark. Among the club’s foreign players, Krall said the team is still trying to work through the logistics of getting Strop back from the Dominican Republic.

Because of the pandemic, MLB clubs have been given unique circumstances in trying to put together a team for a 60-game season with a three-week training camp. Just as challenging will be keeping players and staff healthy. All will be responsible to limit the spread of the virus.

“You don’t want to ruin the season for someone else,” Krall said. “I don’t want to go out and do something and test positive and then give it to somebody else and then you shut down a roster. That would be disastrous. No one wants to do that. I probably speak for all of our staff when I say that, and players. We have a team we think can come out and win this year and be a solid Major League team. We want to do everything in our power to give it the best opportunity and chance to succeed.”