The Orioles emphasized pitching depth when setting their initial player pool for the 2020 MLB season, including 26 arms in their pool of 44 players expected to report to summer camp at Camden Yards on Wednesday. By leaving 16 of the allotted 60 spots open for now, the O's gave themselves flexibility to add prospects to their pool at a later date.

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For now they are set to open camp with 44 in the fold, having to whittle that number down to 30 by Opening Day on July 23 or 24. Per MLB rules, teams must slice their rosters to 28 after 14 days of regular season play, and 26 after 29 days. Additionally, each club can carry up to a three-person taxi squad on the road once the regular season begins.

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The Orioles will hold their main camp at Oriole Park in Baltimore, and are expected to host a satellite camp for prospects at one of their Minor League affiliate sites. The specifics of those plans have yet to be finalized. Players not on the active roster do not accrue Major League service time, so prospect clocks do not start unless they’re added to the active roster during the regular season.

That’s important to note when considering the most notable omissions from the Orioles’ initial pool: No. 4 prospect per MLB Pipeline Ryan Mountcastle and No. 11 prospect Keegan Akin, who were optioned to Triple-A shortly before the coronavirus pandemic struck, but were expected to debut in 2020. Neither will be part of what is essentially the club’s second big league camp. The same is true for the club's top prospect Adley Rutschman, No. 2 Grayson Rodriguez and No. 7 Yusniel Diaz, who were unlikely to debut this year, but will probably be added in the coming weeks.

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The Orioles also officially placed Trey Mancini (colon cancer treatment) on the 60-day injured list in what amounted to a paper move. He will miss the entire season while undergoing chemotherapy treatment. Other non-prospects who were left off the initial pool but are candidates to join later include reliever Evan Phillips, who was sidelined this spring with an elbow injury, outfielders Cedric Mullins and Mason Williams, infielder Richard Ureña and catcher Taylor Davis.

Here is the full breakdown of the Orioles original 44-man player pool:

Catchers (4): Bryan Holaday, Pedro Severino, Chance Sisco, Austin Wynns

The eight-year veteran Holaday was making inroads towards cracking the Opening Day roster when camp was halted, looking like the potential backup to Severino, who hit 13 home runs as the O’s primary catcher in 2019. It was shaping up to be an important year for Sisco, who has struggled on both sides of the ball over parts of three big league seasons. He’ll likely compete with Holaday for the backup job, with Wynns providing depth behind them.

Infielders (10): Hanser Alberto, Chris Davis, Dilson Herrera, José Iglesias, Richie Martin, Renato Núñez, Rio Ruiz, Pat Valaika, Andrew Velazquez, Stevie Wilkerson

The O’s utility competition was hard-fought all spring, with Velazquez and Valaika pushing the incumbent option Martin. Expanded rosters could provide a path for all three to Opening Day. Otherwise, Davis (first base), Alberto (second base), Iglesias (shortstop), Ruiz (third base) and Nunez (designated hitter) are more or less secure at their respective positions.

Outfielders (4): Austin Hays, Anthony Santander, Dwight Smith Jr., DJ Stewart

Labels are deceiving here. With Mancini, the Orioles will technically trek on with only four full-time outfielders in the fold. But other players are certain to see time there as well. Valaika, Velazquez, Herrera and Wilkerson are all versatile enough to play the outfield, with Velazquez and Wilkerson sporting experience in center field. They were moved around all spring and will get reps at a variety of positions again in summer camp.

On the everyday front, Stewart and Smith should compete to see who’ll get the lion share of reps in right field in place of Mancini, whose absence probably provides more opportunity for Mountcastle somewhere down the line as well. Hays and Santander enter summer camp the overwhelming favorites in center and left field after exciting performances in 2019.

Starting pitchers (10): John Means, Alex Cobb, Asher Wojciechowski, Wade LeBlanc, Tommy Milone, Kohl Stewart, Hector Velázquez, Thomas Eshelman, Rob Zastryzny, Cesar Valdez

The Orioles used 18 starters across 162 games in 2019. They’re including enough depth here to, in theory, get them through a 60-game slate without hindering the developmental plans for some of their more highly-regarded young arms. The fifth starter competition was an intrigue of camp, but it was pretty much solidified by the time the coronavirus pandemic struck, with non-roster veterans LeBlanc and Milone carving out likely back-end roles.

Stewart is another option, and Velazquez, Eshelman, Zastrynzny, Valdez (and some in the reliever pool) profile as swingmen, with the ability to provide length whether it is at the start of games or in the middle innings. The most intriguing name in this category may be Valdez, a 35-year-old right-hander who last appeared in the Majors in 2017. He pitched five scoreless innings of mostly mop-up duty when brought over from Minor League camp this spring.

Relief pitchers (16): Shawn Armstrong, Ty Blach, Richard Bleier, Cody Carroll, Miguel Castro, Paul Fry, Mychal Givens, Eric Hanhold, Hunter Harvey, David Hess, Branden Kline, Travis Lakins, Tanner Scott, Chandler Shepherd, Cole Sulser, Dillon Tate

The Orioles carried a nine-man bullpen for stretches last season; expanded rosters could enable them to play with a bloated relief corps yet again if they wished, likely full of swingman candidates that can both start and relieve. Of the full-time relievers more or less reserved spots, it's expected Givens, Harvey, Armstrong, Bleier, Castro and Fry will largely reprise their 2019 roles. Harvey could graduate to closer duties by season’s end, allowing manager Brandon Hyde to deploy Givens in high-leverage situations regardless of inning. Carroll emerged as a back-end option this spring after missing all of 2019 with back issues. Castro and Scott are breakout candidates, and Hess, Shepherd, Tate and even Kline profile as potential multi-inning options.