SEATTLE -- The Mariners set their 60-man player pool that will take part in the resumption of Spring Training, and the group doesn’t include injured outfielder Mitch Haniger, though it does feature a number of top prospects in addition to all 37 players currently on the team’s 40-man roster.

Haniger was placed on the 45-day injured list at the Sunday afternoon deadline as he continues recovering from lumbar microdiscectomy surgery on a herniated disc that was performed on Feb. 13. Haniger could potentially be added back to the active roster as early as mid-August, if he can get healthy.

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The club also released outfielder Carlos González and left-hander Wei-Yin Chen, two veterans who were in the earlier Spring Training camp on Minor League contracts. They're both now free agents.

The 60 invited players are arriving in Seattle this weekend and must pass a COVID-19 test before reporting on Wednesday. The team is expected take the field in divided groups for the first time on Friday at T-Mobile Park to open a three-week summer camp in preparation for the start of the 60-game regular season on July 23 or 24.

Outfielders Jarred Kelenic and Julio Rodriguez, the club’s top-two ranked prospects per MLB Pipeline, are among the invited players who aren’t on the 40-man roster. Also included were the team’s last three first-round Draft picks -- right-handed pitchers Logan Gilbert, George Kirby and Emerson Hancock.

Hancock was just drafted earlier this month. The Mariners also have invited fellow 2020 Draft picks Zach DeLoach, Kaden Polcovich and Tyler Keenan.

Noelvi Marte, an 18-year-old shortstop out of the Dominican Republic, is the youngest invited player and among the group of 10 who weren’t in the initial big league camp earlier this spring as the club looks to get as much work in for its top prospects as possible in the abbreviated season.

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Teams will be allowed to open the season with an expanded 30-man roster, with that group required to be reduced to 28 players after 14 days and then to 26 after 29 days of regular-season play.

Players who are part of the 60-player pool but not on the 30-man Opening Day roster won’t receive Major League service time unless they are added to the Major League roster at some point. Once the Mariners set their regular-season roster, the remaining players will work out together at Tacoma’s Cheney Stadium and play some intrasquad games against each other, but won’t participate in formal games.

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Here are the 60 Mariners invitees: (^ - indicates not on 40-man roster)

Catchers (5): Tom Murphy, Austin Nola, Joe Hudson ^, Brian O’Keefe ^, Cal Raleigh ^

As long as they stay healthy, Murphy and Nola are the two who’ll make the regular-season roster, but it’ll be interesting to see what mandatory third catcher the club brings as part of the required three-player taxi squad that will make all road trips and be available if needed.

Infielders (16): J.P. Crawford, Dee Gordon, Sam Haggerty, Shed Long Jr., Tim Lopes, Dylan Moore, Kyle Seager, Daniel Vogelbach, Donovan Walton, Evan White, Patrick Wisdom, Tyler Keenan ^, José Marmolejos ^, Noelvi Marte ^, Kaden Polcovich ^, Austin Shenton ^

If all goes to plan, it’ll be White, Long, Crawford and Seager as the starting unit, with Vogelbach at designated hitter. But the Mariners have plenty of flexibility in a backup group that will include Gordon as well as likely several of the utility contenders in Lopes, Moore and perhaps Marmolejos if he continues impressing as he did in the earlier camp.

Outfielders (7): Braden Bishop, Jake Fraley, Kyle Lewis, Mallex Smith, Jarred Kelenic ^, Julio Rodriguez ^, Zach DeLoach ^

With Haniger sidelined at least for the first 20 or so games, that leaves Lewis, Smith and Fraley as the likely starters and Bishop backing up. Kelenic and Rodriguez will continue getting good looks, but won’t likely make the big league roster unless there are injuries.

Starting pitchers (14): Justin Dunn, Marco Gonzales, Kendall Graveman, Yusei Kikuchi, Nick Margevicius, Justus Sheffield, Taijuan Walker, Isaiah Campbell ^, Logan Gilbert ^, Emerson Hancock ^, George Kirby ^, Ljay Newsome ^, Juan Then ^, Brandon Williamson ^

To help ease the burden of the limited buildup time, they’ll use a six-man rotation to start the season and that likely allows Dunn to grab the extra spot behind Gonzales, Kikuchi, Graveman, Sheffield and Walker. Gilbert appears first in line among the young prospects, but that group primarily will be using the time just to stay active and gain experience.

Relievers (18): Dan Altavilla, Gerson Bautista, Brandon Brennan, Nestor Cortes, Carl Edwards Jr., Zac Grotz, Taylor Guilbeau, Yoshihisa Hirano, Matt Magill, Yohan Ramirez, Erik Swanson, Art Warren, Taylor Williams, Austin Adams ^, Sam Delaplane ^, Joey Gerber ^, Aaron Fletcher ^, Anthony Misiewicz ^

The expanded 30-man roster opens the door for extra bullpen help early, but this remains an area of interesting competition with so many promising youngsters in the mix. Adams currently is on the 60-day injured list, so not on the 40-man roster. But he’s believed fully recovered now from left knee surgery and should be big part of the Opening Day group if he remains healthy.

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.