SAN DIEGO -- The Padres unveiled their player pool for the 2020 season on Sunday, and the group is jam-packed with big-name prospects – not that you’d expect anything less from Padres general manager A.J. Preller, who has never been shy about challenging young players.

The club's top 13 prospects were all among the 52 players listed, including five from MLB Pipeline's top 100 overall list -- pitchers MacKenzie Gore and Luis Patiño, catcher Luis Campusano, infielder CJ Abrams and outfielder Taylor Trammell. To top it off, the Padres also included Robert Hassell III, the 18-year-old outfielder who was drafted No. 8 overall just three weeks ago.

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“The main thing is getting ready to put a competitive team on the field for the 2020 season,” Preller said. “That’s our primary focus, getting our guys ready for a 60-game season. But obviously we value the development side of things as well. We’re getting some players down in the Minor League system, some guys we feel have bright futures in front of them, getting them some time to come to San Diego, be part of camp, continue to work on their craft and progress toward the Major Leagues.” 

The 60-man player pool represents the group of players who will be able to play for the Padres this season, and San Diego left eight spots open on its initial list. Thirty players will make up the initial Opening Day roster for each team, with that number lowering to 28 after two weeks and 26 after four. The remaining players will train at an alternate site, which the Padres have yet to announce.

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.

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“Summer camp” is set to begin Friday. The Padres anticipate about 35-40 players training at Petco Park with the remaining players (mostly prospects) at a second location, which is expected to be the University of San Diego. The full list of Padres invitees is below. But first, a few key takeaways:

• There are three glaring position-player omissions from this list: second baseman Brian Dozier and outfielders Juan Lagares and Abraham Almonte. All three were squarely on the roster bubble when camp was halted in mid-March. They remain under contract and can still be added to the team's player pool. But it's unclear if the Padres intend to do so.

• Three players on the Padres 40-man roster were omitted from the player pool, none of them surprising. Right-handers Andres Muñoz and Anderson Espinoza are on the mend from Tommy John surgery, while outfield prospect Jorge Oña had little chance of making the big league club this season anyway. Oña, who had been working out at the team’s Spring Training complex in Peoria, Ariz., is still a candidate to be added to the player pool later.

• It was always unlikely that the Padres would need to use 60 players to complete a 60-game season (having used only 54 to complete the full 2019 campaign). That's why Preller didn't hesitate to invite youngsters such as Hassell, outfielder Hudson Head, infielder Tucupita Marcano and lefties Ryan Weathers and Joey Cantillo. No one from that group is expected to crack the big league club this season. But they're all highly regarded prospects who the team believes might benefit from a bit more development.

• Abrams probably belongs in that group, too. But given his elite wheels, there might be an outside chance that the 19-year-old speedster could work his way onto the roster mix as a pinch-runner extraordinaire – especially considering that extra innings will begin with a runner on second base. That seems like a long shot, according to sources.

Here’s the full list of 52 players:

Catchers (5): Austin Hedges, Francisco Mejía, Luis Torrens, Luis Campusano, Webster Rivas

The new roster rules should make catcher one of the Padres' most fascinating positional battles next month. The starting role is still up for grabs between Hedges and Mejía. But with the addition of a designated hitter, Mejía's prospects change a bit. And if Mejía -- a bat-first catcher -- is going to serve as DH, the Padres might opt to carry a third-string catcher like Torrens. If they choose to do so, they'll have extra roster spots to work with for the first four weeks of the season.

Infielders (12): Manny Machado, Eric Hosmer, Fernando Tatis Jr., Ty France, Jurickson Profar, Greg Garcia, Jake Cronenworth, Breyvic Valera, Owen Miller, CJ Abrams, Gabriel Arias, Tucupita Marcano

The absences of Brian Dozier and Gordon Beckham, who was released just before the roster freeze, help clear up the second-base picture a bit. Profar is the presumed starter, with Garcia likely to fight for playing time -- especially against right-handed pitching. Meanwhile, Miller, Cronenworth and Valera could still earn a utility spot. Perhaps no player will benefit more from the addition of a designated hitter than France, whose path to playing time was blocked by Machado and Hosmer at the infield corners.

Outfielders (9): Tommy Pham, Wil Myers, Trent Grisham, Josh Naylor, Franchy Cordero, Taylor Trammell, Edward Olivares, Hudson Head, Robert Hassell III

Barring any further shakeups or injuries, the Padres seem destined for an outfield mix that includes Pham, Myers, Grisham, Naylor and Cordero. Trammell, who had a solid spring but was unlikely to make the club, might still make a case for a sixth man in the outfield. But without Lagares and Almonte, the outfield picture seems to have cleared up.

Starting pitchers (12): Chris Paddack, Dinelson Lamet, Garrett Richards, Zach Davies, Joey Lucchesi, Cal Quantrill, Ronald Bolaños, MacKenzie Gore, Luis Patiño, Jerad Eickhoff, Joey Cantillo, Ryan Weathers

Gore and Patiño, two of baseball's top pitching prospects, will draw plenty of attention in camp, and deservedly so. But if the Padres opt for a five-man rotation, it's unlikely that they crack the Opening Day roster. Paddack, Lamet, Richards, Davies and Lucchesi had established themselves as the likeliest starting five during Spring Training, with Quantrill as a potential swing man. It's hard to see that changing over the next three weeks. Then again, Gore and Patiño are not among the prospects invited merely for development. If they perform, the Padres will almost certainly find meaningful big league innings for them in 2020.

Relief pitchers (14): Kirby Yates, Emilio Pagán, Drew Pomeranz, Matt Strahm, José Castillo, Craig Stammen, Javy Guerra, Pierce Johnson, Gerardo Reyes, Trey Wingenter, David Bednar, Michel Baez, Adrian Morejon, Luis Perdomo

The bullpen was already the Padres' biggest strength in 2020 year. But in a 60-game season with only three weeks for starting pitchers to ramp up, it might prove more valuable than ever. It's unclear how many relief pitchers the Padres will carry for their late-July opener, but it's safe to expect at least nine and possibly as many as 11. They clearly have options. Multi-inning weapons such as Strahm, Pomeranz and Stammen (and potentially Quantrill, if he doesn't win a starting job) could prove especially valuable.